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Someone if I recall had problems with a fuel pump or fuel pump parts from ebay. do a search

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I remember a guy using Seafoam once and having similar problems for a few weeks afterwards. Turns out his plugs where fouled, but that would not be intermittent.

On another note, keep in mind that each of the two ignition cassettes (coil packs as you call them) have an ICM and 4 separate coils.

One other thing that baffles me and raises red flags is that nicked wire, 8" down line and under tape. Gotta wonder how that happened and what else may be lurking farther down line.

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Someone if I recall had problems with a fuel pump or fuel pump parts from ebay. do a search

Good call! I did research, the Global Automotive Products, many, many complaints. The TRE Product, many Kudos, touted to be better than Walbro and much quieter. On Ebay $69 however, another site has them for $49......versus $172. I wish I could have found something to replace paying $96 for a coil bank connector!!!! Little piece of plastic.

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I remember a guy using Seafoam once and having similar problems for a few weeks afterwards. Turns out his plugs where fouled, but that would not be intermittent.

On another note, keep in mind that each of the two ignition cassettes (coil packs as you call them) have an ICM and 4 separate coils.

One other thing that baffles me and raises red flags is that nicked wire, 8" down line and under tape. Gotta wonder how that happened and what else may be lurking farther down line.

The nick was close to the connector, I went another 8" beyond that and all was well. I am not sure what you mean ICM and 4 seperate coils? This is one piece that fits on the spark plugs and cost $200 bucks not like the old $20 buck apiece with a module.
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Each cassette has 4 coils in it. One for each plug, hence COP (Coil On Plug) ignition. The 4 coils are not individually replaceable until later years (maybe '05 or so?). The ICM (Ignition Control Module) is the part that the connector plugs into on the side and is replaceable separately.

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The shop was too busy to check fuel pressure. When I am doing these WOTs would that not put more demand on Fuel? I am in second gear at 6,500 rpms, shift and I am at 100 mph, no misfire. Due to fact that Seafoam spray helped yesterday, I put a can in the tank today and did another run with WOTs. On my return trip (25 miles), no SES, no misfire, no idle roughness........until I pulled into drive and let it idle and it went rough. I recently did a trip to grocery store; rough idle, but catches right away. Sometimes at stop rough idle, sometimes not! Does not make sense and is driving me crazy. One thing is that the Seafoam has made it better, no misfire on highway, or really it seems about 2000rpm, is that a clue? I don't know. I have never seen anything like it incredibly frustrating. I have never had a hiccup with this engine. I don't think fuel, I think electric or some kind of stubborn carbon, valve stick?, It appears to me that when go rough it is 4 cyclinders; but now it catches very quickly and drives off smooth?????????? Any ideas at all are appreciated? Perhaps a exorcism? I had a 94 bonneville before this 347,000 miles, everything perfect, leather, everything. Developed a just cut off; restart run perfect, cut off. Took it everywhere, did every test you can do, took it to dealer, no one could fix....ended up selling for Junk! At least this one doesn't cut off in the middle of expressway in rush hour traffic!!!

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You know to me, diagnostics is a process of elimination. Its not congecture. For me?, it takes 5 minutes to check my fuel pressure, I walk into my garage, grab my gage and hook it up, so its NOT a BIG issue or problem or $60 expense or hassle its DONE and I can quickly eliminate the FN fuel pump and probably the fuel pressure regulator.

I don't diagnose without testing,

To me, diagnostics is an INVERTED CONE, at the beginning you have 100 things that can cause a problem and you eliminate them one by one by testing and at the end you are left with the problem.

For the record, while its nice that you appear to be getting results from the sea foam, we dont advise using it, it has cause members big headaches. That said maybe you have a clogged injector (s) that shows itself at idle.

what was the result of your testing of the injector resistance? How did you test the fuel pressure regulator?

You have just said you don't think fuel, you think electrical or mechanical (valve). the point of checking fuel pressure was to eliminate fuel interruptions from something like the fuel pump relay cutting out or bad ground AT IDLE speeds. At lower RPMs the fuel pump will cycle, if there is a pump start up problem, you will get fuel interruptions. Again, for me, that is a 5 minute test, for you, its a problem.

I would get a probe to check your coil pack to see if its output is dimished by something if you think its spark related.

Here is a schematic for the front bank, check the 20A fuse/relay for corrosionand the ground at G103. Also, I am not sure, is the ICM part of the coil pack assembly?

post-2998-131749626511_thumb.gif

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

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Thanks much! I do not have a fuel pressure gage. I will check fuses. I do have new Codes, 031, 032, 155, 02 Sensors. ??? Perhaps from WOTs? Just went for Pizza. No idle issue going, coming back rough idle at light, next two lights not, next light rough, rest of way home, no rough idle. I will check fuses, don't know how to check resistance for injector. Thanks again.

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Thanks much! I do not have a fuel pressure gage. I will check fuses. I do have new Codes, 031, 032, 155, 02 Sensors. ??? Perhaps from WOTs? Just went for Pizza. No idle issue going, coming back rough idle at light, next two lights not, next light rough, rest of way home, no rough idle. I will check fuses, don't know how to check resistance for injector. Thanks again.

P0031 - Heated Oxygen Sensor (HO2S) Heater Circuit Low Voltage Bank 1 Sensor 1

P0032 - Heated Oxygen Sensor (HO2S) Heater Circuit High Voltage Bank 1 Sensor 1

P0155 - Heated Oxygen Sensor (HO2S) Heater Performance Bank 2 Sensor 1

This is the gage I have from Sears

http://www.sears.com/shc/s/p_10153_12605_00902169000P?prdNo=1&blockNo=1&blockType=G1

WOTs dont cause codes. Something is going on, ill look in the manual and let you know what I find out

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

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At lower RPMs the fuel pump will cycle

Are you sure of this Mike? I've never heard of that. My understanding is that it runs continuously and the unneeded fuel is returned to the tank via the FPR.

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At lower RPMs the fuel pump will cycle

Are you sure of this Mike? I've never heard of that. My understanding is that it runs continuously and the unneeded fuel is returned to the tank via the FPR.

You could very well be correct Ranger

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

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I don't understand. Are we pointing to fuel pump? I check FPR and it works. If I go buy a gage, will that tell me about the fuel pump? I believe it has to maintain 45psi???? The sending unit is bad this I know and have code. No code for fuel pump though........thanks

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A weak or intermittant fuel pump will not set a code. I believe I was clear above about why I was saying to check fuel pressure.

This problem and the interaction within this thread is beyond my capabilities, I cant help anymore, good luck to you, it might be best to take it to a dealer or maybe someone else had an idea

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

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Why the O2 sensor codes suddenly showed up is odd, clear codes and see if they come back

You say you checked the FPR and it works? WHAT DOES THAT MEAN? How did you DETERMINE that it works?

It is NOT a matter as to whether it works it is a matter as to whether with the vacuum hose off it spits fuel at idle and when revved it spits fuel, any evidence of fuel its bad.

It works tells us nothing, the answer is, THERE IS NO PRESENCE OF FUEL

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/

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I pulled off vaccuum hose no fuel at FPR. At the urging of my new best buddy, I went out and bought a new fuel pressure tester, nice one, $55 bucks. It took only a minute to hook it up and fuel pressure with key on engine off is 40psi......when I started let is go to rough, it was 38psi. My understanding is that it should be consistant and between 41 and 47?? What is next? Do I check relay? Where is it? or order new fuel pump assembly, sending unit is bad as I noted earlier. Again, to members here thank you for your great help........and patience!

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I pulled off vaccuum hose no fuel at FPR. At the urging of my new best buddy, I went out and bought a new fuel pressure tester, nice one, $55 bucks. It took only a minute to hook it up and fuel pressure with key on engine off is 40psi......when I started let is go to rough, it was 38psi. My understanding is that it should be consistant and between 41 and 47?? What is next? Do I check relay? Where is it? or order new fuel pump assembly, sending unit is bad as I noted earlier. Again, to members here thank you for your great help........and patience!

Those pressure readings are perfectly fine. Don't replace the fuel pump unless you follow Texas Jim's advice and find the pressure falling way off.

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I pulled off vaccuum hose no fuel at FPR. At the urging of my new best buddy, I went out and bought a new fuel pressure tester, nice one, $55 bucks. It took only a minute to hook it up and fuel pressure with key on engine off is 40psi......when I started let is go to rough, it was 38psi. My understanding is that it should be consistant and between 41 and 47?? What is next? Do I check relay? Where is it? or order new fuel pump assembly, sending unit is bad as I noted earlier. Again, to members here thank you for your great help........and patience!

Key off 40 psi and when it was idling it was 38 psi correct? I gather from what you are saying that when it went rough there was no change in pressure correct?

You are correct, the manual states that it should be between 41 and 47 psi, but I don't think your pressure is low enough to cause a problem, we see high 30's often. I would just store that in the back of your head and do some more fuel pressure testing and watch the gage closely for any drop when the roughness occurs.

I want you to do a test, with the gage attached, and the engine idling, make note of the pressure, and pull the vacuum hose off the fuel pressure regulator. The pressure should jump, what does it jump to?

See this article and you will understand why you needed to know what your fuel pressure is, note the first paragraph

http://www.aa1car.com/library/fuel_pump_diagnose.htm

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/

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I conducted tests twice. Hose is not long enough to tape gage to windshield, but I drove in driveway with hood up. Rough Idle 38, smooth 36, pull hose on FPR and jumps to 41.....car starts with a touch of key....Today perhaps because engine is cool it would cycle from rough to smooth without touching it within a minute. It starts smooth, goes rough, smooth. Does this mean that pump is OK? Where is ground wire for front bank injectors? Where does it attach? Thanks again folks, I do appreciate all.

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I conducted tests twice. Hose is not long enough to tape gage to windshield, but I drove in driveway with hood up. Rough Idle 38, smooth 36, pull hose on FPR and jumps to 41.....car starts with a touch of key....Today perhaps because engine is cool it would cycle from rough to smooth without touching it within a minute. It starts smooth, goes rough, smooth. Does this mean that pump is OK? Where is ground wire for front bank injectors? Where does it attach? Thanks again folks, I do appreciate all.

I gave you a diagram above that shows the coil pack grounded, but I am not 100% sure how, maybe its grounded to the ICM, and you will notice that the ICM is also grounded at G103.

G103 is located at Right rear of the engine, below the exhaust gas recirculation valve.

G103 is #1 in this diagram that is attached

If you can isolate which wire is supplying power to the coil pack you might also check the voltage with a voltmeter. If you get a chance try to find out if the front bank is still misfiring

post-2998-131765581897_thumb.gif

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

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I want to add that the location above that states that G103 is located "at Right rear of the engine, below the exhaust gas recirculation valve" does NOT sound correct to me even though it came out of the manual.

From the drivers position, the EGR is located at the LEFT rear of the engine, someone correct me if I am wrong.

It is possible that a ground was left loose or not attached so look around carefully.

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

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NEW, NEW, code 354 #4 misfire, BUT I am wiggling connector to #4 injector. It appears, that when I wiggle #4 injector it smooths out, but will return to rough. I am pushing the injector to the right and smooths out. That injector is directly below the coil pack connector. We used to wiggle coil pack connector and get smooth. I have inspected the connector and I do not see anything wrong. So...perhaps intermittent injector? ..........or connector. ??? maybe close now?

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You said P0354, do you mean, P0304?

P0354 - Ignition Coil 4 Control Circuit

If you can jiggle the connector and cause problems, it can be a bad connection at the injector or it can be that the fuel rail is not fully seated in the front as you spoke of multiple misfires in the front bank. I would first lift the fuel rail, inspect the injector o-rings, and replace if necessary and reseat the injector rail, UNLESS you are 100% sure its the connector or injector itself, then diagnose that problem

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

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