Not holding idle upon start up
#1
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Not holding idle upon start up
88 N/A, only has 103k miles on it, Automatic - I never had this problem before; but now (no matter what weather, hot or cold) when I crank her over to start, takes two tries, and then when she fires up I get 1k RPM for normal warm up procedure, then it tries to slip, and lows out and dies if I don't rev a little, applying gas to keep her a'float.
Any ideas what I might be experiencing? Need a new fuel filter and oil filter or what?
-my plugs and wires are new and good-
Thanks,
PS is it normal to see the engine smoke a little after a hard drive? Went 50 miles in about 25mins (don't laugh if that's nothing to you) -segments of 120mph- 80average, 100 on and off spurts. (Had heater on, and have TII hood) parked and had to fan the hood a little, was smoking - kinda smelled like coolant really... but I can't see why I would be, I just got a new Rad, and hoses and clamps, and all the components are holding pressure properly, we used that air pump thing, and no leaks... This was only a week ago erm,
Again thanks for trouble shooting,
Have a nice day folks,
Any ideas what I might be experiencing? Need a new fuel filter and oil filter or what?
-my plugs and wires are new and good-
Thanks,
PS is it normal to see the engine smoke a little after a hard drive? Went 50 miles in about 25mins (don't laugh if that's nothing to you) -segments of 120mph- 80average, 100 on and off spurts. (Had heater on, and have TII hood) parked and had to fan the hood a little, was smoking - kinda smelled like coolant really... but I can't see why I would be, I just got a new Rad, and hoses and clamps, and all the components are holding pressure properly, we used that air pump thing, and no leaks... This was only a week ago erm,
Again thanks for trouble shooting,
Have a nice day folks,
#2
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If engine is running smoothly but just idles low or cuts out I would look at the IAC on the throttle body to see if it is working correctly.
If you haven't changed your fuel filter in the last 40K miles or so I would change it anyway.
Smoking from under the hood is never normal. If it smells sweet it is probably coolant. Just chase it down and find the leak. Some things just won't leak until they are hot even if you pump it up with a pressure tester with engine cold.
If you haven't changed your fuel filter in the last 40K miles or so I would change it anyway.
Smoking from under the hood is never normal. If it smells sweet it is probably coolant. Just chase it down and find the leak. Some things just won't leak until they are hot even if you pump it up with a pressure tester with engine cold.
#4
Had similar problems myself
Warg,
I am still trouble shooting a similar problem with my 85 GSL-- it didn't wanna hold idle for the life of it.... Ultimately, what ended up working for me was turning up the idle speed on the carb... it idles soundly now at 1200 rpm, which is a little high, I know, but at least she holds her own now until I can find the real underlying problem... I'm gunna change spark plugs and wires and while I'm at it, makes sure the timing is working right...mine sounds like it is misfiring. I'll let you know if I find anything that may be related to your problem.
I am still trouble shooting a similar problem with my 85 GSL-- it didn't wanna hold idle for the life of it.... Ultimately, what ended up working for me was turning up the idle speed on the carb... it idles soundly now at 1200 rpm, which is a little high, I know, but at least she holds her own now until I can find the real underlying problem... I'm gunna change spark plugs and wires and while I'm at it, makes sure the timing is working right...mine sounds like it is misfiring. I'll let you know if I find anything that may be related to your problem.
Last edited by roresc; 05-15-10 at 07:40 PM.
#5
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Make sure the cold start cam assembly on the throttle body is working, and that the coolant hoses to the throttle body are in place.
Check the BAC to make sure it is plugged in.
Check the ASV for the same.
Check the BAC to make sure it is plugged in.
Check the ASV for the same.
#6
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Thanks guys,
PS also wanted to add to my initial post... as I didn't state that when I keep her rev'd for about 15sec then she can hold her idle like normal, and I've been able to drive her around and what not... it's just annoying to have a three crank and rev requirement to get moving haha
Just throwing it out there, but one of my friends said that since I ran on 91fuel for this last couple months that I might have been why I'm experiencing this... like a Automatic can't run that rich fuel or something... Anyway - Yah I have to change my fuel filter too,
I will check what you all recommended, and report back what the case was. And best of luck to the fellow having start up idle issues as well.
Just throwing it out there, but one of my friends said that since I ran on 91fuel for this last couple months that I might have been why I'm experiencing this... like a Automatic can't run that rich fuel or something... Anyway - Yah I have to change my fuel filter too,
I will check what you all recommended, and report back what the case was. And best of luck to the fellow having start up idle issues as well.
Last edited by WargFC88; 05-18-10 at 01:08 AM.
#7
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This sounds like the typical water thermo sensor problem. It is probably just that the connector backs off of the pins on the sensor. It is on the back side of the thermostat housing. There is a two-pin connector with a wire retaining clip (which you might be missing).
If the computer does not see the water thermo sensor signal, it defaults to an assumed temp (176F I have been told). The computer uses the temp signal to determine how much to richen the mixture for start and cold operation; without it, the mixture is too lean, and it takes a long time to start, and may not start at all. Once running, it is too lean until it is warmed up, which is why it dies once it drops to normal idle. After it warms up (i.e. 195F), it runs slightly too rich.
If you reset the connector and still have the problem, it might be a bad sensor, or an open in the wiring. There is a test procedure in the FSM to determine that the sensor is working properly; but, I just open up the right hand floor and get to the ECU connectors, and backprobe the pin and see that the voltage agrees with the values published in the table in ch4 of the FSM.
While you are in there, back probe all the other connections, and see if any of the others are out of range...
If the computer does not see the water thermo sensor signal, it defaults to an assumed temp (176F I have been told). The computer uses the temp signal to determine how much to richen the mixture for start and cold operation; without it, the mixture is too lean, and it takes a long time to start, and may not start at all. Once running, it is too lean until it is warmed up, which is why it dies once it drops to normal idle. After it warms up (i.e. 195F), it runs slightly too rich.
If you reset the connector and still have the problem, it might be a bad sensor, or an open in the wiring. There is a test procedure in the FSM to determine that the sensor is working properly; but, I just open up the right hand floor and get to the ECU connectors, and backprobe the pin and see that the voltage agrees with the values published in the table in ch4 of the FSM.
While you are in there, back probe all the other connections, and see if any of the others are out of range...
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