Two Questions
Thread Starter
Heel & Toe
Joined: Jan 2007
Posts: 17
Likes: 0
From: Byram Ms
Two Questions
Hello all, Need some help please. I have a 93, automatic that’s been giving me a bit of a problem, surging idle, stumbling, and stumbling under heavy acceleration when cruising at about 60 mph. These problems are intermittent and are not throwing any codes. After reading some of The posts here on the forum from members having similar issues I’m thinking it’s the IAC valve, fuel injectors, EGR valve or the opti-spark. Two questions, am I on the right track? And will a hand held scanner like the autoxray be able to pin point the problem without the check engine light being on or any codes stored? Thanks
Last edited by Bob07; Feb 20, 2008 at 11:25 PM.
Former Vendor
Joined: Nov 2006
Posts: 2,482
Likes: 3
From: Carmichael ca
On the optispark you'll have to remove the cap and look for carbon tracking or water in the cap, not easy to get to. You can check the resistence of the injectors,should be around 12 ohms. I would check the fuel pressure also, 40-45 psi.
Hope this helps, Paul
Hope this helps, Paul
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Hello all, Need some help please. I have a 93, automatic that’s been giving me a bit of a problem, surging idle, stumbling, and stumbling under heavy acceleration when cruising at about 60 mph. These problems are intermittent and are not throwing any codes. After reading some of The posts here on the forum from members having similar issues I’m thinking it’s the IAC valve, fuel injectors, EGR valve or the opti-spark. Two questions, am I on the right track? And will a hand held scanner like the autoxray be able to pin point the problem without the check engine light being on or any codes stored? Thanks
Byram is close to Jackson if I remember. I lived close to Magee for a long time while growing up.
Thread Starter
Heel & Toe
Joined: Jan 2007
Posts: 17
Likes: 0
From: Byram Ms
Thanks for the reply guys. I'll try to check the injectors and the fuel pressure. What are the steps in checking the ohms on the fuel injectors? Will I be checking the injectors or the electrical connector that connects to the injectors?
Yes, you are correct. Byram is just south of Jackson.
Yes, you are correct. Byram is just south of Jackson.
Racer
Joined: Sep 2007
Posts: 393
Likes: 0
From: Bartonville Illinois
Sounds like you might be running out of gas. I haven't had the problem myself yet but maybe your fuel pump is not keeping steady pressure. This used to happen on the old mechanical pumps all the time.
I would look to one problem, fuel pressure, before suspecting 8 bad injectors.
I would look to one problem, fuel pressure, before suspecting 8 bad injectors.
Thread Starter
Heel & Toe
Joined: Jan 2007
Posts: 17
Likes: 0
From: Byram Ms
Ok guys, tested the injectors last night. 7 of the fuel injectors read out at 12.0 to 12.1 ohms, the read out would bounce up to 12.1 and back down to 12.0 but mostly stayed at 12.0 (is that normal?).
one of the injectors read out at 11.9, is this low enough to cause a problem? I will hopefully be able to check the fuel pressure tonight.
one of the injectors read out at 11.9, is this low enough to cause a problem? I will hopefully be able to check the fuel pressure tonight.
Former Vendor
Joined: Nov 2006
Posts: 2,482
Likes: 3
From: Carmichael ca
Ok guys, tested the injectors last night. 7 of the fuel injectors read out at 12.0 to 12.1 ohms, the read out would bounce up to 12.1 and back down to 12.0 but mostly stayed at 12.0 (is that normal?).
one of the injectors read out at 11.9, is this low enough to cause a problem? I will hopefully be able to check the fuel pressure tonight.
one of the injectors read out at 11.9, is this low enough to cause a problem? I will hopefully be able to check the fuel pressure tonight.
Paul
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Thread Starter
Heel & Toe
Joined: Jan 2007
Posts: 17
Likes: 0
From: Byram Ms
I was able to check the fuel pressure today and here is what I got.
The first time I check it with the ignition in the on position and the reading was 40 psi. The second and third time with the ignition on the reading was 38 psi. Next I tested it with the car idling and the needle on the pressure gage was very erratic, it bounced back and forward between 36 and 40 psi very rapidly, so fast that I could not get a good reading, I did not notice any drop in the pressure after a few minutes of idling. I was wondering if this was normal (the bouncing needle) so I hooked the fuel pressure gage up to my truck and started it up and the needle on the gage was smooth. Do this mean that my fuel pump is bad or maybe the regulator? Help... please
The car has approx. 105,000 miles on it.
The first time I check it with the ignition in the on position and the reading was 40 psi. The second and third time with the ignition on the reading was 38 psi. Next I tested it with the car idling and the needle on the pressure gage was very erratic, it bounced back and forward between 36 and 40 psi very rapidly, so fast that I could not get a good reading, I did not notice any drop in the pressure after a few minutes of idling. I was wondering if this was normal (the bouncing needle) so I hooked the fuel pressure gage up to my truck and started it up and the needle on the gage was smooth. Do this mean that my fuel pump is bad or maybe the regulator? Help... please
The car has approx. 105,000 miles on it.
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
This truly sounds like a bad opti (classic symptoms) especially with that mileage. The injectors of that year and later hold up very well unlike the injectors of the earlier years of the late 80s. Fuel pressure also sounds just fine, it does fluctuate.With that kind of mileage on the opti its probably wiser to replace the whole unit in regard to the amount of work to get at it. The bearings also wear and can produce wobble. There is probably corrosion on the optical disk and the optical pickups can deteriorate over time and heat.
