Car idleing rough/ dies when I give it gas
Full Member
Joined: May 2003
Posts: 87
Likes: 0
From: SF Bay Area, CA USA
Originally Posted by MarkPerez
it's the fuel filter, get a new one and problem solved. period !
I live in an igloo
Joined: Jul 2004
Posts: 2,546
Likes: 0
From: calgary alberta
First thing that came to my mind is that it was running way to rich, and when you give it gas it stalls becuase its so rich and becuase your cats/air filter or both are clogged.
If it stinks like gas, check your o2 sensor. If your o2 sensor is new then you probably have really shitty leaky injectors.
It could also be an afm problem too.. so many things to try and narrow it down. your gonna have to spend the day diagnosing to see what the hell is up.
If it stinks like gas, check your o2 sensor. If your o2 sensor is new then you probably have really shitty leaky injectors.
It could also be an afm problem too.. so many things to try and narrow it down. your gonna have to spend the day diagnosing to see what the hell is up.
Lives on the Forum
Joined: Feb 2004
Posts: 5,721
Likes: 3
From: Coldspring TX
Originally Posted by glorthu
The last thing I did before this happened, besides take it on a nice drive through the mountains, was replace a couple resistors in the ECU. They were related to the catalyst air supply.
Haven't tried putting it in gear or pulling codes. It was in gear (on the highway), however when it first started having this problem.
I just checked the AFM using the FSM proceedure. It checked out okay, but I have one concern. When I checked the resistance between E2 and Vs, it was within specs (50-500 ohms) fully open and fully closed (~460 and 80 ohms respectively), but when it was halfway open, it went up to over 1000 ohms. Is this normal? Looking at the diagram, E1 and Fc tell whether the flapper is fully open, and E2 to Vs should give the position of the flapper. I would have guessed it should go smoothly from one resistance to another as the flapper is pushed open, not go up and then down...
Haven't tried putting it in gear or pulling codes. It was in gear (on the highway), however when it first started having this problem.
I just checked the AFM using the FSM proceedure. It checked out okay, but I have one concern. When I checked the resistance between E2 and Vs, it was within specs (50-500 ohms) fully open and fully closed (~460 and 80 ohms respectively), but when it was halfway open, it went up to over 1000 ohms. Is this normal? Looking at the diagram, E1 and Fc tell whether the flapper is fully open, and E2 to Vs should give the position of the flapper. I would have guessed it should go smoothly from one resistance to another as the flapper is pushed open, not go up and then down...
And since the ECU repairs were related to the port air and/or split air solenoids, have you checked them out for correct operation?
I noticed my AFM doing that weird resistance thing also when I was playing with it during the rebuild. I can't explain it other than to say it's normal. If in doubt read the AFM's input at the ECU while running, where you should see a nice linear voltage during throttle transitions with no "hiccups".
Full Member
Joined: May 2003
Posts: 87
Likes: 0
From: SF Bay Area, CA USA
Checked the ECU. One of the resistors I had replaced had fried itself again. Unfortunately I had replaced the 1 watt 3.9 ohm resistor with a 5 watt 3.9 ohm resistor (all that was available locally), and the heat it generated seems to have melted some neighboring components. This resistor is for the split-air solenoid (2K), so I guess there is a short there somewhere.
The resistor didn't fail entirely though (it still read 4.9 ohms even fried as it was), so I'll try running the car with that resistor removed just in case...
The resistor didn't fail entirely though (it still read 4.9 ohms even fried as it was), so I'll try running the car with that resistor removed just in case...
Lives on the Forum
Joined: Feb 2004
Posts: 5,721
Likes: 3
From: Coldspring TX
The split-air and port air solenoids are famous for shorting out and taking the wiring (and ECU) with them. Since you hail from Cali, you're going to have to get 'em fixed before emissions, but at this point just try disconnecting the solenoids' connectors out on the ACV to see if that helps with the problem...
Lives on the Forum
Joined: Feb 2004
Posts: 5,721
Likes: 3
From: Coldspring TX
If your solenoid coils are shorted out on the ACV, all you're gonna do is fry another ECU...
The problem with troubleshooting this kind of thing is that coils damn near act like a short when read with a meter anyway, so you may not realize that they're bad. And most of the time, it takes a good current flow to turn them into "Mr Hyde", and you can't do that with a normal meter...
Another way to tell would be to look at the wiring coming from both of the solenoids out on the ACV. If any of the wires look like they've been overheated, that's your bad guy...
The problem with troubleshooting this kind of thing is that coils damn near act like a short when read with a meter anyway, so you may not realize that they're bad. And most of the time, it takes a good current flow to turn them into "Mr Hyde", and you can't do that with a normal meter...
Another way to tell would be to look at the wiring coming from both of the solenoids out on the ACV. If any of the wires look like they've been overheated, that's your bad guy...
Full Member
Joined: May 2003
Posts: 87
Likes: 0
From: SF Bay Area, CA USA
Removing the split air and port air solenoids didn't change anything. The wires to the split air solenoid looked pretty crispy though, so I'm pretty sure it, at least, will need to be replaced. I just hope my wiring harness isn't fubar.
Thread
Thread Starter
Forum
Replies
Last Post
alphawolff
1st Generation Specific (1979-1985)
17
Nov 17, 2015 05:57 PM
smikels
2nd Generation Specific (1986-1992)
3
Aug 18, 2015 01:26 PM
