Scotty Posted September 30, 2005 Report Share Posted September 30, 2005 No codes. Smell is from the fumes-rich. No smoke. Did not have the TB, ISC or TPS off. It will run fine for a while then start acting up again. Some times when I come to a stop, or just going down the road. Checked the FPR, no fuel coming from it. I've replaced just about everything on this car. What is the procedure for replacing the TPS. For some reason I can't use the search now and google isn't any help. Do I just unhook the batt and replace the TPS? The TPS will give you a code, just don't replace it. Check the connections at the PCM again. When you replaced the PCM you were happy right? It was OK at that point? That is way too coincidental. You have checked grounds? If the PCM connections are ok, think about the pick up in the distributor. I for some reason have to think that this is PCM related, OR... you need to do an extensive adjustment of the MINIMUM AIR TPS and ISC motor The procedure is in the manual Link to comment Share on other sites More sharing options...
Ranger Posted October 1, 2005 Report Share Posted October 1, 2005 There is a proceedure for adjusting the ISC motor after replacement or I beleive before the idle learn proceedure. If I remember correctly it goes like this. Raise the idle enough to get your finger on the ISC plunger and press on it til it retracts all the way in. When it stops, unplug it. At that point the engine should just barely idle at about 450 RPM and may even die. Now adjust the ISC plunger out to the throttle stop and then back it off and lock it in place with a gap of either .030 or .060 (I can't recall for sure. Anyone remember?). Then do th4e idle learn. Link to comment Share on other sites More sharing options...
Scotty Posted October 1, 2005 Report Share Posted October 1, 2005 Thanks Ranger Link to comment Share on other sites More sharing options...
PAUL T Posted October 1, 2005 Report Share Posted October 1, 2005 Scotty, You're not gonna believe this. I have to reset my idle learn just about every time I drive and some times I have to stop on a trip to reset it. Some times it works and some times it doesn't. Car is now running very rough, idles up and down, so rich it makes your eyes water and kills no telling how many brain cells, like I have any to spare (LOL). And mileage is out the door. TPS maybe? This thing doesn't have a MAP sensor does it? How are you checking the FPR? Are you pulling the hose off while the engine is running or checking it with the hose off then turning the key on to pressurize the fuel system? If you are just pulling the hose off while the car is not running or the key on you probably will not see fuel. I would bet with all the rich smell would be the FPR, gas or no gas leaking it still could be bad. You might check to see if all the injectors are seated good. Idle learn is not really necessary all the time, the computer will relearn itself after a few starts anyway. Link to comment Share on other sites More sharing options...
tommyjack Posted October 4, 2005 Author Report Share Posted October 4, 2005 I would think if it were the FPR it would not be intermittent. This thing misses, surges, runs rough, some times idles up and down, runs very rich and shutters. Then it will smooth out and run great for a few miles. I did unhook the EGR vacuum hookup and did not get any codes. I even drove it that way for about 25 miles and it made no difference. Does this mean anything? Link to comment Share on other sites More sharing options...
Logan Posted October 4, 2005 Report Share Posted October 4, 2005 Did you ever check the front engine ground near the starter? Also, did take the bolts out of the battery cables and inspect for corosion? Logan Diagnostic LLC www.airbagcrash.com www.logandieselusa.com www.ledfix.com www.ledfix.com/yukontaillightrepair.html www.ledfix.com/ledreplacements.html www.ledfix.com/j42385toolrental.html Link to comment Share on other sites More sharing options...
tommyjack Posted October 4, 2005 Author Report Share Posted October 4, 2005 I checked all the grounds per the chart. I did not undo the bolts on the batterty. I have however had them undone several times and everything looked good. Link to comment Share on other sites More sharing options...
Logan Posted October 4, 2005 Report Share Posted October 4, 2005 You should take apart and clean the lower front engine ground (4.9L). Its near the starter. Just looking at it is not enough. Common Cadillac issue with those engines. Another idea may be a bad intermitant cell in the battery. Logan Diagnostic LLC www.airbagcrash.com www.logandieselusa.com www.ledfix.com www.ledfix.com/yukontaillightrepair.html www.ledfix.com/ledreplacements.html www.ledfix.com/j42385toolrental.html Link to comment Share on other sites More sharing options...
Oldgamer Posted October 4, 2005 Report Share Posted October 4, 2005 tommyjack, I hope you reinstall your old PROM from PCM into new one. If you didn't do so, it can be a problem. I'm not sure that it is, but just in case, pull out PROM from old PCM and install into new PCM. Link to comment Share on other sites More sharing options...
Scotty Posted October 4, 2005 Report Share Posted October 4, 2005 You should take apart and clean the lower front engine ground (4.9L). Its near the starter. Just looking at it is not enough. Common Cadillac issue with those engines. Another idea may be a bad intermitant cell in the battery. Good Ideas Logan Tommy has been through everything! Its going to be something quirky... I had a bad battery in my 4.9 and it would not pull away from the curb.... as soon as I gave it gas, it just died... I had NEVER seen anything like that before.. so its entirely possible that if the battery is intermittant, you could have ignition problems. I have never seen an intermittant battery, Logan, have you seen that? Mine battery had dead cells, can they be intermittant also? Link to comment Share on other sites More sharing options...
adallak Posted October 4, 2005 Report Share Posted October 4, 2005 You should take apart and clean the lower front engine ground (4.9L). Its near the starter. Just looking at it is not enough. Common Cadillac issue with those engines. Another idea may be a bad intermitant cell in the battery. A new stud (8 mm) and star washers would help. The saddest thing in life is wasted talent Link to comment Share on other sites More sharing options...
tommyjack Posted October 4, 2005 Author Report Share Posted October 4, 2005 I really appreciate everyones help and suggestions. The new ECM/PCM etc... came without the PROM so I had to use my old one. I may just be me but it seems that when this thing is running OK (very rare) and I come to a stop or a bump in the road it starts acting up. May just be me. Any way I have an old 4.9 that I know had good parts on it so I just replaced the TPS and ISC from it on to may ride and there was no improvement. The old ISC was making a rachet sound and needed replaced anyway. The car did run OK for a few minutes after I replaced it, then it went back to its old miss, rough idle, shuttering again. To recap: Problem-rough idle, poor fuel mileage(16MPG was 27), shuttering when trying to come up to speed(driving), raw fuel smell. Runs like this most of the time then will suddenly clear up( when this happens it feels like a 50HP shot of nitrious). Runs this way a few miles then then back to the missing, etc... To recap the following have been replaced: Cap/Rotor/Wires/Plugs Distributor Fuel Filter ECM ISC TPS Injectors Both O2 sensors Checked fuel pressure 36 PSI at idle, 36 when key is on then drops quickly to 0 Checked FPR-No fuel coming from FPR when car is running Checked EGR- push up on bottom and car stalls Cleaned grounds to the battery. Will check the ohters tomorrow. Link to comment Share on other sites More sharing options...
Oldgamer Posted October 4, 2005 Report Share Posted October 4, 2005 Ok, I can't see something else in that long list... the coil. Did you try to replace coils with a new one? You can do that one by one. Link to comment Share on other sites More sharing options...
tommyjack Posted October 4, 2005 Author Report Share Posted October 4, 2005 Sorry, Coil was replaced with cap, rotor, etc... 4.9 only has 1 coil. Link to comment Share on other sites More sharing options...
Scotty Posted October 4, 2005 Report Share Posted October 4, 2005 The think that bothers me is that it ran good after the PCM was replaced. Did you check the nearby grounds near the PCM when you changed it? Its probably NOT your imagination that a BUMP fudges it up. Check the grounds. Did you look at the connectors in the wire harness for damage, looseness, green, corrosion, rust? You have OBDI have you tried looking at realtime parameters when you are having problems. The only problem with that is that if something was wrong you would set a code. It has to be something that does not set a code. Check the connection at the distributor, I had to replace my connector as one of the wings broke off. Is the distributor tight? The distributor acts as the CAM sensor also. Is the distributor installed correctly, see below. Also check the battery!! Link to comment Share on other sites More sharing options...
Logan Posted October 5, 2005 Report Share Posted October 5, 2005 There is actually a bulletin about using a new washer on the ground. The main thing is to take it apart and at least clean it. They can 'look' ok.... Bad batteries and Cadillacs dont mix. I have seen several ones with a bad cell. Even my fake DTS one had a bad cell. It would qwirk every so often. I knew right away it was a bad cell. Logan Diagnostic LLC www.airbagcrash.com www.logandieselusa.com www.ledfix.com www.ledfix.com/yukontaillightrepair.html www.ledfix.com/ledreplacements.html www.ledfix.com/j42385toolrental.html Link to comment Share on other sites More sharing options...
tommyjack Posted February 10, 2006 Author Report Share Posted February 10, 2006 After about five pages of posts and lots of part changes I finally took it to the stealer ship and had it put on the computer. Only to tell me the computer is bad. I had replaced it some where in the trouble shooting process, it didn't fix the problem so I ASSUMED it was not the problem. What I didn't know is that I got a bad computer from the parts store. $65.00 to the dealer and a trip to the store and I had a new compuuter (under warranty) that works. Problem solved as far as the miss goes. But it acts like it has a carb on it when I first start it. Cold natured. I guess I need to do the idle learn or adjust the ISC. Thanks for everyone who helped out. And remember, the electric part you get new may not always work as advertised!!! TJ Link to comment Share on other sites More sharing options...
PAUL T Posted February 10, 2006 Report Share Posted February 10, 2006 The computer will adjust itself if you do not due the Idle Learn. It should smooth out after a while. Good Luck! Link to comment Share on other sites More sharing options...
BodybyFisher Posted February 10, 2006 Report Share Posted February 10, 2006 I am glad you narrowed the problem down.... Thanks for reporting back your findings.. Mike Pre-1995 - DTC codes OBD1 >> 1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/ Cadillac History & Specifications Year by Year http://www.motorera.com/cadillac/index.htm Link to comment Share on other sites More sharing options...
BodybyFisher Posted February 10, 2006 Report Share Posted February 10, 2006 The think that bothers me is that it ran good after the PCM was replaced. Tommy, as you can see, Scotty could not understand why it ran good after the PCM was replaced!!! We were right on this problem!!! Too bad the new PCM went bad that was the problem all along and we finally nailed it by replacing the PCM.. Not much you can do about a bad part, a bad part can throw you WAY off track... Mike Scotty is me by the way! Pre-1995 - DTC codes OBD1 >> 1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/ Cadillac History & Specifications Year by Year http://www.motorera.com/cadillac/index.htm Link to comment Share on other sites More sharing options...
tommyjack Posted February 10, 2006 Author Report Share Posted February 10, 2006 Thanks guys. I thought I would post the final result. I know I searched through about every thread on here and found a lot had the same problem but they rarely posted what the final corrective action was. I'l besure and remember your new name Scotty, er a Bodybyfisher. Link to comment Share on other sites More sharing options...
adallak Posted February 10, 2006 Report Share Posted February 10, 2006 Thanks guys. I thought I would post the final result. I know I searched through about every thread on here and found a lot had the same problem but they rarely posted what the final corrective action was. I'l besure and remember your new name Scotty, er a Bodybyfisher. ScottybyFisher The saddest thing in life is wasted talent Link to comment Share on other sites More sharing options...
BodybyFisher Posted February 10, 2006 Report Share Posted February 10, 2006 Pre-1995 - DTC codes OBD1 >> 1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/ Cadillac History & Specifications Year by Year http://www.motorera.com/cadillac/index.htm Link to comment Share on other sites More sharing options...
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