Diagnose this???
Thread Starter
Le Mans Master
Joined: Feb 1999
Posts: 9,916
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From: South Carolina
St. Jude Donor '03 & '05
Diagnose this? IT WAS definitely the OPTI..
I just got off the highway, and the car started running real choppy (real rich). I put new plugs in, checked injectors for operation (good), all spark plug wires working, no codes (EGR electronically shut off via chip).
Ran DIACOM, barely idles, but have data if interested. It is actiing like it is in LIMP mode, but with no codes.
Motor has less than 1000 miles, OPTI is a 95 unit, HOT CAM, 396, ED Wright chip, plugs blacker than doo-doo (dry black), tried 2 different ignitions(factory and MSD), no mechanical noises, it is just msiing real bad. Please help if you can. Steve
[Modified by steve40th, 7:26 PM 9/29/2002]
[Modified by steve40th, 5:36 PM 10/1/2002]
Ran DIACOM, barely idles, but have data if interested. It is actiing like it is in LIMP mode, but with no codes.
Motor has less than 1000 miles, OPTI is a 95 unit, HOT CAM, 396, ED Wright chip, plugs blacker than doo-doo (dry black), tried 2 different ignitions(factory and MSD), no mechanical noises, it is just msiing real bad. Please help if you can. Steve
[Modified by steve40th, 7:26 PM 9/29/2002]
[Modified by steve40th, 5:36 PM 10/1/2002]
Team Owner
Joined: Dec 2000
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From: SE NY
Cruise-In II Veteran
Re: Diagnose this??? (steve40th)
Look at your O2 sensor(s) and see if it/they are laying flat (likely low), with no oscillation between .3V & .9V.
Also see if it shows loop status as closed loop mode.
Also see if it shows loop status as closed loop mode.
Safety Car
Joined: Aug 2002
Posts: 3,842
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From: SANTA CRUZ CA
Re: Diagnose this??? (steve40th)
Damn, Steve. If you didn't have a new opti, that would be my first guess as the source of your problem. Without DTC's, a diagnosis is very difficult, especially with all the corrective measures you have taken. I have a '93 GM manual for reference, if you don't.
(Served a year at the Navy radio station, Wahiawa, many years ago)
(Served a year at the Navy radio station, Wahiawa, many years ago)
Thread Starter
Le Mans Master
Joined: Feb 1999
Posts: 9,916
Likes: 38
From: South Carolina
St. Jude Donor '03 & '05
Re: Diagnose this??? (Oldman)
I checked the O2's and already replaced them. I have the data, but I cant read on my computer, excel is gone, but on Diacom the O2's were around 450mv.
I am thinking OPTI. It was stored sionce May, and only driven 3 times. It drove fine, even made arun down the track last night. I walked it out then hit in 3rd, 13.2 114mph. Ran good, till I got off the Hoghway. FP is at 42psi, without vacuum.
I am at a loss. Injectors were at 3.5 (30# SVO's) and BLM was 128, INT wat 110 all at idle.
[Modified by steve40th, 3:45 PM 9/29/2002]
I am thinking OPTI. It was stored sionce May, and only driven 3 times. It drove fine, even made arun down the track last night. I walked it out then hit in 3rd, 13.2 114mph. Ran good, till I got off the Hoghway. FP is at 42psi, without vacuum.
I am at a loss. Injectors were at 3.5 (30# SVO's) and BLM was 128, INT wat 110 all at idle.
[Modified by steve40th, 3:45 PM 9/29/2002]
Safety Car
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From: Sun City West Az
Re: Diagnose this??? (steve40th)
What was the intergrator readings? Did the FP drop when you hooked up the vacuum line at idle? Check the EECS system, especially the soleniod to see if it's cycling the canister rather than stuck open. Injector resistance within 1 OHM of each other? Just some thoughts.
Thread Starter
Le Mans Master
Joined: Feb 1999
Posts: 9,916
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From: South Carolina
St. Jude Donor '03 & '05
Re: Diagnose this??? (ittlfly)
The integreator readings were 110, BLM 128. This was after it was warmed up. SO the motor was still Hot. I dont have th einjector resistance, but I have the DIACOM file showing the engine at idle, if you would like it.
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Safety Car
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From: Sun City West Az
Re: Diagnose this??? (steve40th)
It sounds like a fuel problem. You might ohm out all your injectors to see if they are within 1 ohm of each other.(possible shorted injector soleniod problem). Did you check the EECS soleniod for sticking open? That would continously purge your canister vapors into the intake enriching the mixture. With the intergrator at 110 and the blms at 128, shows a short term correction going on with the system in control. also check the voltage out of the alternator. That will raise hvoc with the ECM if not within specs. And lastly, the fuel pump...???
BTW, we're headed for "The Big Island" tomorrow morning for aweek....so aloha ,and hope you get the problem resolved :seeya
[Modified by ittlfly, 6:42 PM 9/30/2002]
BTW, we're headed for "The Big Island" tomorrow morning for aweek....so aloha ,and hope you get the problem resolved :seeya
[Modified by ittlfly, 6:42 PM 9/30/2002]
Thread Starter
Le Mans Master
Joined: Feb 1999
Posts: 9,916
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From: South Carolina
St. Jude Donor '03 & '05
Re: Everything points to the opti, but why so fast? (BBA)
"It sounds like a fuel problem. You might ohm out all your injectors to see if they are within 1 ohm of each other.(possible shorted injector soleniod problem). Did you check the EECS soleniod for sticking open? That would continously purge your canister vapors into the intake enriching the mixture. With the intergrator at 110 and the blms at 128, shows a short term correction going on with the system in control. also check the voltage out of the alternator. That will raise hvoc with the ECM if not within specs. And lastly, the fuel pump...???"
The EECS solenoid? How do I check that? I also disconnected the injectors one at a time and no change. But how else can I check the injectors with a volt meter?
Fuel Pump is a GM "Grand National" unit about 1 1/2 old.
The EECS solenoid? How do I check that? I also disconnected the injectors one at a time and no change. But how else can I check the injectors with a volt meter?
Fuel Pump is a GM "Grand National" unit about 1 1/2 old.
Thread Starter
Le Mans Master
Joined: Feb 1999
Posts: 9,916
Likes: 38
From: South Carolina
St. Jude Donor '03 & '05
Re: Everything points to the opti, but why so fast? (steve40th)
I took the OPTI out , and when I spun it the noise was definitely not good.
It rattled and I could here pieces moving around that werent attached to anything. So hopefully, When the new one comes tommorow, and I replace it, I hope it fixes it. Thanks for all the help, Steve
It rattled and I could here pieces moving around that werent attached to anything. So hopefully, When the new one comes tommorow, and I replace it, I hope it fixes it. Thanks for all the help, Steve
