Jump to content
CaddyInfo Cadillac Forum

Work In Progress...


Recommended Posts


  • Replies 147
  • Created
  • Last Reply

Well I'm pretty sure that my problem is indeed my MAP sensor itself, not the wiring, but I could be wrong. I still feel...blah... and didn't have the ambition to go out and change it today, but amidst my travels to the store in my father-in-law's car, I made a pit stop at my car in the driveway. I got in, turned the key on, ignition off, entered diagnostics, and set the PCM data display to PD02 (MAP sensor) as mentioned in a previous post in this thread. Here are steps 1-3.

1.) "ignition on" enter diagnostics

select PCM DATA PD02 (Map Sensor)

Note display

2.) 20 to 84 kPa

Replace MAP sensor

3.) 85 to 105 kPa

Remove intake cover

Connect vacuum source to MAP sensor

Note PCM Data parameter PD02 as you slowly apply vacuum

to the sensor up to 20". Each 1" of vacuum should result in a 3 to 4

kPa drop in PD02.

Watch for a skip or jump in parameter PD02 value. A skip or jump indicates a bad MAP sensor

With 20" of vacuum applied note PD02 Parameter

My display read 10kPa. I started the car, and it started but ran very poorly and at a very low idle. The MAP reading did not budge from 10kPa. Within about 30 seconds, it stalled. With that fact noted, I don't see a need to bother with the rest of the diagnostic for it. I would say my MAP is dead. It's reading lower than the replacement values mentioned in step 2. Tomorrow is supposed to be a little warmer than it has been, and I'm feeling a little better, so I think I may just go out and change this thing. Hopefully after this, I will have no more trouble. We shall see.

Does anyone think this could still be a wiring issue?

big4870885.jpg

Link to comment
Share on other sites

Well I'm pretty sure that my problem is indeed my MAP sensor itself, not the wiring, but I could be wrong. I still feel...blah... and didn't have the ambition to go out and change it today, but amidst my travels to the store in my father-in-law's car, I made a pit stop at my car in the driveway. I got in, turned the key on, ignition off, entered diagnostics, and set the PCM data display to PD02 (MAP sensor) as mentioned in a previous post in this thread. Here are steps 1-3.

1.) "ignition on" enter diagnostics

select PCM DATA PD02 (Map Sensor)

Note display

2.) 20 to 84 kPa

Replace MAP sensor

3.) 85 to 105 kPa

Remove intake cover

Connect vacuum source to MAP sensor

Note PCM Data parameter PD02 as you slowly apply vacuum

to the sensor up to 20". Each 1" of vacuum should result in a 3 to 4

kPa drop in PD02.

Watch for a skip or jump in parameter PD02 value. A skip or jump indicates a bad MAP sensor

With 20" of vacuum applied note PD02 Parameter

My display read 10kPa. I started the car, and it started but ran very poorly and at a very low idle. The MAP reading did not budge from 10kPa. Within about 30 seconds, it stalled. With that fact noted, I don't see a need to bother with the rest of the diagnostic for it. I would say my MAP is dead. It's reading lower than the replacement values mentioned in step 2. Tomorrow is supposed to be a little warmer than it has been, and I'm feeling a little better, so I think I may just go out and change this thing. Hopefully after this, I will have no more trouble. We shall see.

Does anyone think this could still be a wiring issue?

Carla, I checked the diagnostic tree in my manual for P032 and one of the notes says. "If MAP sensor or circuitry are open, PD02 will read 10-16kPa." So if the new sensor does not change things look for an open wire somewhere close by. It could be that the old sensor has a short in it, lets just hope.

Link to comment
Share on other sites

Thanks. I looked over all the wiring when I had the cover off the first time, and I did find one bare spot, but I covered it with Thermal electrical tape. When I put the new one in I'll keep my eyes open for anything else I may have missed, and check the spot I taped to be sure it didn't come loose for some reason. Is there any need to disconnect the battery during or after changing the MAP sensor? I wouldn't think so, but figured I'd ask anyway.

big4870885.jpg

Link to comment
Share on other sites

If you've got a MAP sensor in your hand, a really good way to check the wiring is to put it in and see if the car is fixed.

CTS-V_LateralGs_6-2018_tiny.jpg
-- Click Here for CaddyInfo page on "How To" Read Your OBD Codes
-- Click Here for my personal page to download my OBD code list as an Excel file, plus other Cadillac data
-- See my CaddyInfo car blogs: 2011 CTS-V, 1997 ETC
Yes, I was Jims_97_ETC before I changed cars.

Link to comment
Share on other sites

If you've got a MAP sensor in your hand, a really good way to check the wiring is to put it in and see if the car is fixed.

That was my original thought too, but my car has seemed "fixed" a few times now, ran perfect for a couple days, then went back to this same stalling issue and throwing a MAP code thing all over again. It seems to be an intermittent problem for the most part. Guess I'll have to try it and hope for the best. Worst case: it runs fine for a few days, then does this again, and I have to start looking deeper into the issue.

big4870885.jpg

Link to comment
Share on other sites

I don't want to celebrate yet, but I think my car is ok now... or at least I really really hope so.

I got the MAP sensor changed tonight (in my driveway, in the FREEZING cold). As soon as I put the new one in, I set the PCM data display to PD02 and the MAP sensor reading was 99kPa. Rechecked all the wiring before putting the manifold cover back on, and everything looked good. After putting the cover on, I cleared all the PCM codes, then started the car and let it run for about 30 minutes. I was revving the engine a few times and letting the idle drop back down to see if it affected how it was running any, and it was running PERFECT! After letting it run for that 30 minutes or so, I checked the codes (SES light wasn't on, but wanted to check anyway) and it said "No PCM Codes". I can't remember the last time I saw that displayed! I also checked the PD02 again, and it was at 55kPa at idle, and would fluctuate when I hit the gas and let off it.

Also, while the hood was open and it was running, my brother and I tried once again to pinpoint the squealing from the water pump belt area. He happened to have a can of mountain dew in his hand, and I swear I almost knocked him out when he dumped a little on the belt. In the midst of my screaming at him for dumping soda in my car, he says "wait, listen...do you hear that?" The squealing had stopped. Apparently none of the pulleys are bad at all, it's just the belt squealing.

Like I said, I don't want to celebrate quite yet, but I think my problem may be cured now. Tomorrow I'll take her for a test drive and see how she runs. So far, so good. I'm keeping my fingers crossed!yupi3ti.gif

big4870885.jpg

Link to comment
Share on other sites

I don't want to celebrate yet, but I think my car is ok now... or at least I really really hope so.

I got the MAP sensor changed tonight (in my driveway, in the FREEZING cold). As soon as I put the new one in, I set the PCM data display to PD02 and the MAP sensor reading was 99kPa. Rechecked all the wiring before putting the manifold cover back on, and everything looked good. After putting the cover on, I cleared all the PCM codes, then started the car and let it run for about 30 minutes. I was revving the engine a few times and letting the idle drop back down to see if it affected how it was running any, and it was running PERFECT! After letting it run for that 30 minutes or so, I checked the codes (SES light wasn't on, but wanted to check anyway) and it said "No PCM Codes". I can't remember the last time I saw that displayed! I also checked the PD02 again, and it was at 55kPa at idle, and would fluctuate when I hit the gas and let off it.

Also, while the hood was open and it was running, my brother and I tried once again to pinpoint the squealing from the water pump belt area. He happened to have a can of mountain dew in his hand, and I swear I almost knocked him out when he dumped a little on the belt. In the midst of my screaming at him for dumping soda in my car, he says "wait, listen...do you hear that?" The squealing had stopped. Apparently none of the pulleys are bad at all, it's just the belt squealing.

Like I said, I don't want to celebrate quite yet, but I think my problem may be cured now. Tomorrow I'll take her for a test drive and see how she runs. So far, so good. I'm keeping my fingers crossed!yupi3ti.gif

Sounds good!

The saddest thing in life is wasted talent

Link to comment
Share on other sites

I would change the water pump belt and check the tensioner.

CTS-V_LateralGs_6-2018_tiny.jpg
-- Click Here for CaddyInfo page on "How To" Read Your OBD Codes
-- Click Here for my personal page to download my OBD code list as an Excel file, plus other Cadillac data
-- See my CaddyInfo car blogs: 2011 CTS-V, 1997 ETC
Yes, I was Jims_97_ETC before I changed cars.

Link to comment
Share on other sites

It will sound even better after I drive it for a few days and don't have any more issues! So far the most I have gotten out of it between working on it has been about 5-6 starts/drives before it started dying again. I'm thinking about driving it until it's (almost) out of gas tomorrow just to be sure it's going to stay running right this time. Of course, I will have to park it and restart it a few times in between, but still.

big4870885.jpg

Link to comment
Share on other sites

I would change the water pump belt and check the tensioner.

I know as much as I can't pull the tensioner by hand. I have tried. And the squealing really sounds like it's coming from the drive pulley, or very close to it. I'm going to change the belt for now. Hopefully everything else will hold out on me at least until warmer weather gets here.unsure.gif

big4870885.jpg

Link to comment
Share on other sites

At that age/mileage on the car, the grease in the belt tensioner bearing dries up and the bearing begins to squeal. The bulley with bearing is available from Rochauto.com for a reasonable price. Every auto part store will want to sell the whole tensioner assembly for $70-100. Use a 1/4" drive breaker bar to release the tension on the belt and spin the tensioner pulley. It should be smooth with a slight resistance. If the pulley spins with no effort or sounds noisy/rough, the bearing is bad.

I second Jim's advice on replacing the water pump belt also. You don't know how many miles are on the belt. If it turns out you need to change the tensioner bearing, belt replacement is a 30 second job at that point.

Kevin
'93 Fleetwood Brougham
'05 Deville
'04 Deville
2013 Silverado Z71

Link to comment
Share on other sites

At that age/mileage on the car, the grease in the belt tensioner bearing dries up and the bearing begins to squeal. The bulley with bearing is available from Rochauto.com for a reasonable price. Every auto part store will want to sell the whole tensioner assembly for $70-100. Use a 1/4" drive breaker bar to release the tension on the belt and spin the tensioner pulley. It should be smooth with a slight resistance. If the pulley spins with no effort or sounds noisy/rough, the bearing is bad.

I second Jim's advice on replacing the water pump belt also. You don't know how many miles are on the belt. If it turns out you need to change the tensioner bearing, belt replacement is a 30 second job at that point.

I already knew it needed a new belt. It's got some pretty bad cracks in it. My tensioner pulley can't be loosened with a breaker bar. I've tried. It has some weird guard thing over the sides of the pulley that don't seem to come off. I posted a picture of it before. Here are the links to them.

http://s305.photobucket.com/albums/nn204/ChevyMetalBitch/Caddy/?action=view&current=tpulley1.jpg

http://s305.photobucket.com/albums/nn204/ChevyMetalBitch/Caddy/?action=view&current=tpulley2.jpg

I definitely need to figure out how to loosen the thing in order to get the belt off and change it, and check the pulley itself.

Going to be taking my car for a test drive/road trip in a little while here to see how it's running otherwise. I'm really hoping this MAP sensor did the trick.

big4870885.jpg

Link to comment
Share on other sites

I'm still not quite ready to celebrate, but I took my car for a 2 hour test run today and put it through everything I could find to. Hills, highway, city, you name it.... the new MAP seems to have cured the stalling issue completely. I'm not getting any more codes for it on the OBD either. HOORAY for that! I also ordered the new water pump belt while I was out. That will be in tomorrow morning.

I do however still have 2 unresolved issues, though neither of them seem major in comparison to what I have been dealing with.

As soon as my car hits about 40-45 mph (it varies from time to time), without fail, the SES light is still coming on. Code P039: TCC/VCC engagement problem. Any advice on how to figure out exactly what is causing this or stop it from happening?

Second, my IPC is still acting up. When I started the car the dash lights for the analog speedo, tach, and gas gauges were out. Then everything: Climate control, DIC, gauge cluster, all of it went out, then came back on. After I drive for a while with the heat on, everything dries out and works fine. There is water getting in there somehow, and I'm not sure where. The whole left side of the dash is soaked when I get in the car to the point that water is dripping from the hood release lever under it.

I can only figure 2 possible causes. 1: The sunroof drain line is clogged and somehow leaking into my dash. or 2: The ice/frost that forms on the inside of the windshield is melting and dripping down into the dash (this doesn't seem likely for there being that much water).

Whatever the cause of the water, I need to get it taken care of before I end up having to replace the whole IPC. Being that it's winter, is there any way to check the sunroof drain line without damaging it?

Overall, the car seems to be running great. It sounds and drives like a completely different vehicle. I never would have thought the MAP sensor could have such a HUGE impact on how the car drives and runs. I just hope it stays running this time.

big4870885.jpg

Link to comment
Share on other sites

Sounds like you nailed it Carla. Congrats.

Every auto part store will want to sell the whole tensioner assembly for $70-100.

Funny this should come up. I just changed the water pump on my wife's '96 Bonneville yesterday. The belt was all wet with Dex and I know from experience that Dex will delaminate a belt so I took it to the car was to power wash it. Before I could back out of the stall it was squealing. I thought it was a wet belt and would soon stop. No such luck. Got home and checked. It was the tensioner pulley. The high pressure spray must have gotten past the seal, but I'm sure it was close to going anyway. I guess after 165K it didn't owe me anything. I have pressed those bearings out and replaced them, but this one was on a plastic pulley and seemed to be molded in place. It wasn't coming out. Called around and Napa had the pulley alone for $27. Autozone had one for $17. Replaced it in :10 min. and she was quiet again.

Link to comment
Share on other sites

As soon as my car hits about 40-45 mph (it varies from time to time), without fail, the SES light is still coming on. Code P039: TCC/VCC engagement problem. Any advice on how to figure out exactly what is causing this or stop it from happening?

Carla, you may have TCC lock-up problem (torque converter). To check its operation maintain steady 55 MPH with your right foot on the gas pedal. At the same time tap slightly the brake pedal with your left foot to engage the brake switch. As soon as the switch is engaged the torque converter should unlock. You can monitor that by watching RPM on your DIC. When torque converter unlocks RPM should jump some 100-150 RPM.

Many have been driving with that problem for a long time. The only side effect will be decreased gas mileage (some 15%).

The saddest thing in life is wasted talent

Link to comment
Share on other sites

As soon as my car hits about 40-45 mph (it varies from time to time), without fail, the SES light is still coming on. Code P039: TCC/VCC engagement problem. Any advice on how to figure out exactly what is causing this or stop it from happening?

Carla, you may have TCC lock-up problem (torque converter). To check its operation. Maintain steady 55 MPH with your right foot on the gas pedal. At the same time press slightly the brake pedal with your left foot to engage the brake switch, As soon as the switch is engaged the torque converter should unlock. You can monitor that by watching RPM on your DIC. When torque converter unlocks RPM should jump some 100-150 RPM.

Many have been driving with that problem for a long time. The only problem will be decreased gas mileage (some 15%).

It's funny you should mention the change in RPM. I noticed today that once the code sets, my RPM's jump about 200 or so and stay there for the rest of the drive until I slow back down. Judging by what you say I am guessing this would mean it isn't locking, or it is, but then quickly unlocking. It doesn't seem to be shifting hard at all or anything like that. I'm wondering if maybe it's just a solenoid issue.

Just for the heck of it, after it set the first time today, I stopped and shut the car off (so the SES light would go away), then started it back up. This time when I started driving, instead of gradually increasing my speed up to 60mph, I laid into the gas HARD until it got up to 60. The SES light didn't come on that time, but once I slowed down and started picking up speed gradually again it did at 45mph. I made a stop while I was out, then on the way home I did the same thing with laying into the gas pedal and again, no SES light.

It would seem from my little "experiment" that it only sets when accelerating at a steady, normal pace.

big4870885.jpg

Link to comment
Share on other sites

As soon as my car hits about 40-45 mph (it varies from time to time), without fail, the SES light is still coming on. Code P039: TCC/VCC engagement problem. Any advice on how to figure out exactly what is causing this or stop it from happening?

Carla, you may have TCC lock-up problem (torque converter). To check its operation. Maintain steady 55 MPH with your right foot on the gas pedal. At the same time press slightly the brake pedal with your left foot to engage the brake switch, As soon as the switch is engaged the torque converter should unlock. You can monitor that by watching RPM on your DIC. When torque converter unlocks RPM should jump some 100-150 RPM.

Many have been driving with that problem for a long time. The only problem will be decreased gas mileage (some 15%).

It's funny you should mention the change in RPM. I noticed today that once the code sets, my RPM's jump about 200 or so and stay there for the rest of the drive until I slow back down. Judging by what you say I am guessing this would mean it isn't locking, or it is, but then quickly unlocking. It doesn't seem to be shifting hard at all or anything like that. I'm wondering if maybe it's just a solenoid issue.

Just for the heck of it, after it set the first time today, I stopped and shut the car off (so the SES light would go away), then started it back up. This time when I started driving, instead of gradually increasing my speed up to 60mph, I laid into the gas HARD until it got up to 60. The SES light didn't come on that time, but once I slowed down and started picking up speed gradually again it did at 45mph. I made a stop while I was out, then on the way home I did the same thing with laying into the gas pedal and again, no SES light.

It would seem from my little "experiment" that it only sets when accelerating at a steady, normal pace.

As far as I remember A and B shift solenoids and TCC lock-up solenoid are the same part number. I would not do anything and would drive like that.

The saddest thing in life is wasted talent

Link to comment
Share on other sites

Is it true that I would have to pull the Trans to change the solenoid? I wish I knew for sure if it was that or the TCC itself that's causing a problem....

I've been driving it for 4 months now like this and no major problems yet. (At least none related to it) I cringe every time I see that SES light now though, lol. I'm so used to it meaning something worse. unsure.gif

big4870885.jpg

Link to comment
Share on other sites

Is it true that I would have to pull the Trans to change the solenoid? I wish I knew for sure if it was that or the TCC itself that's causing a problem....

I've been driving it for 4 months now like this and no major problems yet. (At least none related to it) I cringe every time I see that SES light now though, lol. I'm so used to it meaning something worse. unsure.gif

Carla, unfortunately I do not have my 1991 Seville FSM anymore to check it out. Nevertheless, if it were easy to replace people would rather fix it instead of driving without lock-up. Just drive it! LOL

The saddest thing in life is wasted talent

Link to comment
Share on other sites

Is it true that I would have to pull the Trans to change the solenoid? I wish I knew for sure if it was that or the TCC itself that's causing a problem....

I've been driving it for 4 months now like this and no major problems yet. (At least none related to it) I cringe every time I see that SES light now though, lol. I'm so used to it meaning something worse. unsure.gif

Carla, unfortunately I do not have my 1991 Seville FSM anymore to check it out. Nevertheless, if it were easy to replace people would rather fix it instead of driving without lock-up. Just drive it! LOL

I've been Just Driving it! I just don't want any more little problems that are going to turn into BIG problems. I've had enough of that for a while. On the upside, thanks to this forum and me doing my own work, it only cost me about 250$ in parts to get it running good again, and I don't need to worry about plugs and wires for a while. biggrin.gif

big4870885.jpg

Link to comment
Share on other sites

Is it true that I would have to pull the Trans to change the solenoid? I wish I knew for sure if it was that or the TCC itself that's causing a problem....

I've been driving it for 4 months now like this and no major problems yet. (At least none related to it) I cringe every time I see that SES light now though, lol. I'm so used to it meaning something worse. unsure.gif

Carla, unfortunately I do not have my 1991 Seville FSM anymore to check it out. Nevertheless, if it were easy to replace people would rather fix it instead of driving without lock-up. Just drive it! LOL

I've been Just Driving it! I just don't want any more little problems that are going to turn into BIG problems. I've had enough of that for a while. On the upside, thanks to this forum and me doing my own work, it only cost me about 250$ in parts to get it running good again, and I don't need to worry about plugs and wires for a while. biggrin.gif

Yep, that's not a lot. The most annoying repairs on my 4.9 engine powered Seville were caused with rust. All brake lines, transmission lines, PS lines, heater pipe, gas tank and straps. Many electrical gremlins. The gremlins occurred after my car got flooded though... Did I miss something? :)

Your car is rust-free, so for that alone you should be grateful! lol

The saddest thing in life is wasted talent

Link to comment
Share on other sites

Is it true that I would have to pull the Trans to change the solenoid? I wish I knew for sure if it was that or the TCC itself that's causing a problem....

I've been driving it for 4 months now like this and no major problems yet. (At least none related to it) I cringe every time I see that SES light now though, lol. I'm so used to it meaning something worse. unsure.gif

Carla, unfortunately I do not have my 1991 Seville FSM anymore to check it out. Nevertheless, if it were easy to replace people would rather fix it instead of driving without lock-up. Just drive it! LOL

I've been Just Driving it! I just don't want any more little problems that are going to turn into BIG problems. I've had enough of that for a while. On the upside, thanks to this forum and me doing my own work, it only cost me about 250$ in parts to get it running good again, and I don't need to worry about plugs and wires for a while. biggrin.gif

Yep, that's not a lot. The most annoying repairs on my 4.9 engine powered Seville were caused with rust. All brake lines, transmission lines, PS lines, heater pipe, gas tank and straps. Many electrical gremlins. The gremlins occurred after my car got flooded though... Did I miss something? :)

Your car is rust-free, so for that alone you should be grateful! lol

Oh believe me I am! Even the undercarriage is rust free. I'm also grateful that I found this car for only 500$. It makes it hurt a lot less that the parts are so expensive for it.

big4870885.jpg

Link to comment
Share on other sites

I've been Just Driving it! I just don't want any more little problems that are going to turn into BIG problems. I've had enough of that for a while. On the upside, thanks to this forum and me doing my own work, it only cost me about 250$ in parts to get it running good again, and I don't need to worry about plugs and wires for a while. :D

Just think what it would have cost you, if you were not able to do it yourself.

I would guess, offhand...around $1000...maybe more.

You have done a lot of good troubleshooting and made some nice repairs on your car.

Congratulations to you.

:D

Posted Image
Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.



×
×
  • Create New...