Still a really fast idle
10-07-2003, 07:49 AM
#1
Still a really fast idle
Ok, got almost everything working again...EXCEPT THAT INFERNAL FAST IDLE. Now that the tach is working again, it shows the car is idling at between 2000 & 2500 RPM.
All of the vacuum lines are good. I could not find any loose connections. I tried turning the idle adjust screw, with no results. I also tried disconnecting the Fast Idle Solenoid, with no success. I have not been able to properly check for a leak in the intake lines, but I doubt that one.
The things I'm thinking of are the pressure switch that I need for my rack & pinion, or the ECU going through a "Learning" mode type thing, as it went without any form of power for a couple of months. Possibly even still a bad ECU, but not likely.
The pressure switch mentioned is supposed to read the line pressure from the pressure hose, and feed a resistance signal to the ECU, so that if pressure is low, it would idle the engine up a little, to provide more power assist while idling. Because of this function, I'm doubtful this is the actual case, as it shouldn't idle the engine up that fast.
Any ideas?
All of the vacuum lines are good. I could not find any loose connections. I tried turning the idle adjust screw, with no results. I also tried disconnecting the Fast Idle Solenoid, with no success. I have not been able to properly check for a leak in the intake lines, but I doubt that one.
The things I'm thinking of are the pressure switch that I need for my rack & pinion, or the ECU going through a "Learning" mode type thing, as it went without any form of power for a couple of months. Possibly even still a bad ECU, but not likely.
The pressure switch mentioned is supposed to read the line pressure from the pressure hose, and feed a resistance signal to the ECU, so that if pressure is low, it would idle the engine up a little, to provide more power assist while idling. Because of this function, I'm doubtful this is the actual case, as it shouldn't idle the engine up that fast.
Any ideas?
10-08-2003, 06:41 AM
#2
Well, here's what I managed to get looked at last night before it got dark, and started to rain...
Checked, and re-checked all intake lines for leaks or loose fittings...only found the AIV exhaust feed to be loose at the exhaust manifold...so I tightened that.
I disabled various vacuum lines throughout the engine compartment, while running, and nothing made a difference, so I can rule out a possible vacuum issue.
checked the connector condition on the CHTS, and it was clean, and in good shape.
Triple checked the grounds, and other misc. power lines, and nothing...
After making sure everything was tight, I started it up, and it idled at 1800RPM based on the factory tach. I noticed the gas gause was reading VERY low, so I used the fresh gas for the mower we have left from the mowing season. Wasn't much, but it moved the gauge needle a hair. Tried to start her up, and she just cranked over and over...wouldn't start...waited a few moments, and tried again...same thing...waitewd a few more minutes, and it started up, idled at about 700-800 RPM, but idled VERY rough, and was blowing a LOT of black smoke from the exhaust...tap the gas pedal a bit, revving it up, and it just blew more black smoke, then idled up to 1800-2000 RPM, smoothed back out, and the smoke dissippated...
BTW, during the entire fast idle issue going on, the car is running quite rich...not so much so as to see smoke, but more than enough to smell gas heavily in the exhaust...
My thoughts are, perhaps the old gas isn't burning completely, setting off the O2 sensor. This would cause the ECU to try and ingest more air, which could possibly cause the fast idle. I'm plannign to try and put some fresh gas in the beast this evening, and allow it to run on that, and see if it just needs to purge the crap from the system.
Checked, and re-checked all intake lines for leaks or loose fittings...only found the AIV exhaust feed to be loose at the exhaust manifold...so I tightened that.
I disabled various vacuum lines throughout the engine compartment, while running, and nothing made a difference, so I can rule out a possible vacuum issue.
checked the connector condition on the CHTS, and it was clean, and in good shape.
Triple checked the grounds, and other misc. power lines, and nothing...
After making sure everything was tight, I started it up, and it idled at 1800RPM based on the factory tach. I noticed the gas gause was reading VERY low, so I used the fresh gas for the mower we have left from the mowing season. Wasn't much, but it moved the gauge needle a hair. Tried to start her up, and she just cranked over and over...wouldn't start...waited a few moments, and tried again...same thing...waitewd a few more minutes, and it started up, idled at about 700-800 RPM, but idled VERY rough, and was blowing a LOT of black smoke from the exhaust...tap the gas pedal a bit, revving it up, and it just blew more black smoke, then idled up to 1800-2000 RPM, smoothed back out, and the smoke dissippated...
BTW, during the entire fast idle issue going on, the car is running quite rich...not so much so as to see smoke, but more than enough to smell gas heavily in the exhaust...
My thoughts are, perhaps the old gas isn't burning completely, setting off the O2 sensor. This would cause the ECU to try and ingest more air, which could possibly cause the fast idle. I'm plannign to try and put some fresh gas in the beast this evening, and allow it to run on that, and see if it just needs to purge the crap from the system.
10-08-2003, 10:33 AM
#3
Senior Member
Join Date: Jun 2003
Posts: 380
Originally Posted by MaxWgn
Well, here's what I managed to get looked at last night before it got dark, and started to rain...
Checked, and re-checked all intake lines for leaks or loose fittings...only found the AIV exhaust feed to be loose at the exhaust manifold...so I tightened that.
I disabled various vacuum lines throughout the engine compartment, while running, and nothing made a difference, so I can rule out a possible vacuum issue.
checked the connector condition on the CHTS, and it was clean, and in good shape.
Triple checked the grounds, and other misc. power lines, and nothing...
After making sure everything was tight, I started it up, and it idled at 1800RPM based on the factory tach. I noticed the gas gause was reading VERY low, so I used the fresh gas for the mower we have left from the mowing season. Wasn't much, but it moved the gauge needle a hair. Tried to start her up, and she just cranked over and over...wouldn't start...waited a few moments, and tried again...same thing...waitewd a few more minutes, and it started up, idled at about 700-800 RPM, but idled VERY rough, and was blowing a LOT of black smoke from the exhaust...tap the gas pedal a bit, revving it up, and it just blew more black smoke, then idled up to 1800-2000 RPM, smoothed back out, and the smoke dissippated...
BTW, during the entire fast idle issue going on, the car is running quite rich...not so much so as to see smoke, but more than enough to smell gas heavily in the exhaust...
My thoughts are, perhaps the old gas isn't burning completely, setting off the O2 sensor. This would cause the ECU to try and ingest more air, which could possibly cause the fast idle. I'm plannign to try and put some fresh gas in the beast this evening, and allow it to run on that, and see if it just needs to purge the crap from the system.
Checked, and re-checked all intake lines for leaks or loose fittings...only found the AIV exhaust feed to be loose at the exhaust manifold...so I tightened that.
I disabled various vacuum lines throughout the engine compartment, while running, and nothing made a difference, so I can rule out a possible vacuum issue.
checked the connector condition on the CHTS, and it was clean, and in good shape.
Triple checked the grounds, and other misc. power lines, and nothing...
After making sure everything was tight, I started it up, and it idled at 1800RPM based on the factory tach. I noticed the gas gause was reading VERY low, so I used the fresh gas for the mower we have left from the mowing season. Wasn't much, but it moved the gauge needle a hair. Tried to start her up, and she just cranked over and over...wouldn't start...waited a few moments, and tried again...same thing...waitewd a few more minutes, and it started up, idled at about 700-800 RPM, but idled VERY rough, and was blowing a LOT of black smoke from the exhaust...tap the gas pedal a bit, revving it up, and it just blew more black smoke, then idled up to 1800-2000 RPM, smoothed back out, and the smoke dissippated...
BTW, during the entire fast idle issue going on, the car is running quite rich...not so much so as to see smoke, but more than enough to smell gas heavily in the exhaust...
My thoughts are, perhaps the old gas isn't burning completely, setting off the O2 sensor. This would cause the ECU to try and ingest more air, which could possibly cause the fast idle. I'm plannign to try and put some fresh gas in the beast this evening, and allow it to run on that, and see if it just needs to purge the crap from the system.
is your throttle cable too tight? a long shot, but that might be it...
10-08-2003, 06:04 PM
#4
That has been checked...
When the engine is throttled up, or revved, it doesn't rev down as quickly as it had before...
Also, even after the car has been running for several minutes, the temp gauge never moves...is the temp gauge fed from the CHTS?
When the engine is throttled up, or revved, it doesn't rev down as quickly as it had before...
Also, even after the car has been running for several minutes, the temp gauge never moves...is the temp gauge fed from the CHTS?
10-08-2003, 08:29 PM
#5
No, the temp gauge isn't, the CHTS doesn't come into contact with engine coolant. Meaning that it's possible the coolant temperature sensor is bad, sending unit is bad, or the gauge is bad. Have you gotten a chance to check codes yet?
S
S
10-11-2003, 05:11 PM
#8
Member
Join Date: Mar 2002
Posts: 61
for the fast idle:
Have you tried to disconnect the rubber hoses from the Auxilary Air Regulator and plug in both holes on the intake manifold? (to see if this will drop the idle speed) Sometimes this device gets stuck in the open position and lets extra air through all the time. (You can also test it by removing it from the manifold but leave the regulator plugged in the socket and in about 10 minutes the valve should be closed completely.
Have you tried to lift off the throttle cable form the throttle valve dish to see if the cable or the valve got stuck?
You mentioned that after a rev up the idle speed wil not return to "normal" as quickly as it used to.
In my experience this is a sign of false air in the system, most likely somewhere between the throttle valve and cylinder head.
You can also try one more thing but here you have to be very cautious about fire hazard:
Try to blow carburetor cleaner spray to here and there anywhere between the throttle valve and the cylinder head. (do just very brief spray-puffs at a time and make sure that the spray will never reach the exhaust manifold area!!!)
If there is any leak (false air entry) in the intake system and you happen to hit that area with carburator cleaner, the change in idle speed will quickly indicate the problem area to you.
a)
In case, the rev. will go up for a few seconds, that is a sign of false air, but in this case the mixture is low in idle.
b) in case, the rev. will go down, most likely the mxture is already too rich and the extra fuel (carb. cleaner) just made it even more richer),
This reminds me of something else: If the E.C.U. "thinks" that for whatever reason the engine needs rich fuel-air mixture (like if you lived in Alaska), it might trigger the cold start valve as well.
I would also try to remove the cold start valve (leave the harness on it, plug the hole on the intake manifold and start the engine. (2 persons have to to be there, one who is holding the cold start valve into a jar incase it will start letting fuel out.!!!)
At the same time you can also check if the cold start valve will hold the pressure or starts dripping or peeing when you turn the ignition on and after that when the engine is idling.
But as someone else mentioned it earlier. I think it would be a good idea to check all sensors that feed the E.C.U. (water temp, air temp) and maybe just run the E.C.U. check first.
Geza
P.s.: Important! For all the tests, that involves gas or carb cleaner in open air, you should always have someone with you, plus some blankets and/or fire extinguiser wouldn't hurt either. Also, it's better to do these tests outdoor rather than in a garage.
Have you tried to disconnect the rubber hoses from the Auxilary Air Regulator and plug in both holes on the intake manifold? (to see if this will drop the idle speed) Sometimes this device gets stuck in the open position and lets extra air through all the time. (You can also test it by removing it from the manifold but leave the regulator plugged in the socket and in about 10 minutes the valve should be closed completely.
Have you tried to lift off the throttle cable form the throttle valve dish to see if the cable or the valve got stuck?
You mentioned that after a rev up the idle speed wil not return to "normal" as quickly as it used to.
In my experience this is a sign of false air in the system, most likely somewhere between the throttle valve and cylinder head.
You can also try one more thing but here you have to be very cautious about fire hazard:
Try to blow carburetor cleaner spray to here and there anywhere between the throttle valve and the cylinder head. (do just very brief spray-puffs at a time and make sure that the spray will never reach the exhaust manifold area!!!)
If there is any leak (false air entry) in the intake system and you happen to hit that area with carburator cleaner, the change in idle speed will quickly indicate the problem area to you.
a)
In case, the rev. will go up for a few seconds, that is a sign of false air, but in this case the mixture is low in idle.
b) in case, the rev. will go down, most likely the mxture is already too rich and the extra fuel (carb. cleaner) just made it even more richer),
This reminds me of something else: If the E.C.U. "thinks" that for whatever reason the engine needs rich fuel-air mixture (like if you lived in Alaska), it might trigger the cold start valve as well.
I would also try to remove the cold start valve (leave the harness on it, plug the hole on the intake manifold and start the engine. (2 persons have to to be there, one who is holding the cold start valve into a jar incase it will start letting fuel out.!!!)
At the same time you can also check if the cold start valve will hold the pressure or starts dripping or peeing when you turn the ignition on and after that when the engine is idling.
But as someone else mentioned it earlier. I think it would be a good idea to check all sensors that feed the E.C.U. (water temp, air temp) and maybe just run the E.C.U. check first.
Geza
P.s.: Important! For all the tests, that involves gas or carb cleaner in open air, you should always have someone with you, plus some blankets and/or fire extinguiser wouldn't hurt either. Also, it's better to do these tests outdoor rather than in a garage.
10-13-2003, 07:11 AM
#9
Thanks...I didn't get a chance to do anything this weekend...instead of working on the car, I got a call fomr someone, and ended up spending most of the weekend working on someone's computer...
Didn't get my car fixed, but I earned a couple extra bucks...allowed me to buy the med's my doc scripted to me for my respritory infection...
Didn't get my car fixed, but I earned a couple extra bucks...allowed me to buy the med's my doc scripted to me for my respritory infection...
10-16-2003, 06:52 AM
#10
Welp, the idle's now back to normal...took quadruple checking all hoses and connections, and then simply driving it...being very careful, as right now the brakes suck, with the rotors rusted a little, etc...and with no speedometer...
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