1985 idle issues found problem wont fix?????
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,385
Likes: 4
From: King George VA
1985 idle issues found problem wont fix?????
I have a stumbling bumbling 85 Im working on for a friend. I located the idle issue it was the esc module. I disconnect it while running and it goes away. I connect it the bad idle comes back. I pulled codes before and I had O2 open left side and esc module fault.
I have the new module installed and it didnt fix it. I removed the sensor from it while it was running and it fixed.
So whats before this sensor that it gives it information? Is it the knock sensors?
Im going to pull the codes again maybe reset the computer to give it another chance.
I have the new module installed and it didnt fix it. I removed the sensor from it while it was running and it fixed.
So whats before this sensor that it gives it information? Is it the knock sensors?
Im going to pull the codes again maybe reset the computer to give it another chance.
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,385
Likes: 4
From: King George VA
1)It rides a low idle even if I advance it by turning the distributor.
2)Lights (ALL) flicker when running. Had it tested at advanced, its good.
3)I stepped on it alittle it wakes up but bogs after a second or two. Than the SES light comes on.
4)Read the codes again after battery reset and after a drive. Code 43 came back.
5)Oil pressure isnt reading, stuck at 80 psi.
6)Late shifts or holds out a second.
7) Temps are 190-200 oil and 200-210 coolant.
8) Half the dash lights and functions are malfunctioning.
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
With "all" the lights flickering it makes you wonder about the integrity of main grounding points for the car/block. You might want to pull the terminals on the alternator & battery and clean those up. Does the "volt" gauge work? Good voltage - over 12vdc when running? You may want to wait until dark then pop the hood, fire it up and look for plug wire shorts (arcs).
Last edited by engle1147; Nov 19, 2010 at 03:47 PM.
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,385
Likes: 4
From: King George VA
With "all" the lights flickering it makes you wonder about the integrity of main grounding points for the car/block. You might want to pull the terminals on the alternator & battery and clean those up. Does the "volt" gauge work? Good voltage - over 12vdc when running? You may want to wait until dark then pop the hood, fire it up and look for plug wire shorts (arcs).
Volt gauge works and its on the money. Its getting above 12. I tested it at autozone and it passed all tests. I did that the first night and I found C#1 completely chopped and laying on the header. I ran new wires today cause some were questionable so I replaced them all.
I think grounds are a possibility so I hear there are 11 grounds so Ill check them and clean them all.
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,385
Likes: 4
From: King George VA
Pro
Joined: Mar 1999
Posts: 678
Likes: 0
From: Oslo, Norway
Hi.
I have an 85 an had trouble with the idle. For me it was some issues. First it was the EGR valve and then false air. But still it was not good at all. I checked what you did and the ground was very good. The lights was flickering . I read an article about flickering lights and they came up with the alternator. It could be the voltage regulator that oscillates.
Well the alternator had quite some miles on it so I bought a new one. Flickering stopped and the idle became good. When the flickering occurs (oscillating regulator or even bad diode(s)) tere are voltage riple so high that even the injectors get wrong voltage and ecm and maf all get too much ripple to manage.
Well this was my fix. Hope it can be as easy for yoou. Borrow an alternator you know is good from another car and try it before you buy.
good luck
I have an 85 an had trouble with the idle. For me it was some issues. First it was the EGR valve and then false air. But still it was not good at all. I checked what you did and the ground was very good. The lights was flickering . I read an article about flickering lights and they came up with the alternator. It could be the voltage regulator that oscillates.
Well the alternator had quite some miles on it so I bought a new one. Flickering stopped and the idle became good. When the flickering occurs (oscillating regulator or even bad diode(s)) tere are voltage riple so high that even the injectors get wrong voltage and ecm and maf all get too much ripple to manage.
Well this was my fix. Hope it can be as easy for yoou. Borrow an alternator you know is good from another car and try it before you buy.
good luck
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Melting Slicks
Joined: Nov 2005
Posts: 3,323
Likes: 142
From: Green Valley Arizona
Even though Advanced says the alternator is good....it still may be putting out an AC voltage, caused by one of the diodes going out in the rectifier. If you have a DMM, try putting in on the AC scale and see what it reads.
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,385
Likes: 4
From: King George VA
Well today I did alot. I pulled the plugs and they were all fouled. I replaced that and I did a cap and rotor. Cheap tuneup stuff really. I verified timing. I also did put a knock sensor in. She is running good and responsive not really having a wondering idle. But I still have a code 42.
Any thoughts?
Any thoughts?
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
After you checked timing (assume that you disconnected the single wire by the wiper motor).....did you clear computer codes by disconnecting the battery? When you disconnect the wire to set timing, it sets the code 42.
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,385
Likes: 4
From: King George VA
Yeah i disconnected the single wire. Yeah I disconnected the battery. That sets the 42 code?
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
Sorry, I had to ask.....some times it is the simple things that are overlooked. When you disconnect the single wire to set the timing it set the code 42.
If you are still getting a code 42....it may be the ignition module in the distributor. I believe that there are some auto parts stores that can check your old module to see if it is bad.
If you are still getting a code 42....it may be the ignition module in the distributor. I believe that there are some auto parts stores that can check your old module to see if it is bad.
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 3,385
Likes: 4
From: King George VA
Sorry, I had to ask.....some times it is the simple things that are overlooked. When you disconnect the single wire to set the timing it set the code 42.
If you are still getting a code 42....it may be the ignition module in the distributor. I believe that there are some auto parts stores that can check your old module to see if it is bad.
If you are still getting a code 42....it may be the ignition module in the distributor. I believe that there are some auto parts stores that can check your old module to see if it is bad.
Yeah it clears.... I found that my alternator voltage regulator is bad. Buying a new one tomorrow. Some say that the low voltage that it screws up can give me these problems. I hope it fixes it.
