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Discussion Starter · #1 ·
Hey there... Before you automatically reply with "we've done this a hundred times before" just read on!

My idle speed was really high, usually around 1500-2000... It wouldn't kick down, but eventually if the car idled long enough, it would drop to just under 1000, where it is supposed to be. As soon as I drive or rev at all, the RPMs were back up.

It had just started to fluctuate, as well, in the last week or two, after driving for a while, sitting at a light in neutral, the RPMs would quickly fluctuate between 1500-2500 on a constant loop.

So, last night after work, I set out to drop the idle speed, using the idle air screw on the TB. I dropped it down to around 1100 with accessories off, around 750 with accessories on. It ran smooth as a dream last night and the RPM fluctuation ceased.

This morning was really the first time that it was cold enough, the car was frosted over, so I went out and started it up about 10 minutes early to let it heat up, turn the rear defrost on, etc.

When I got back in the car 10 minutes later, the gas fumes were so thick in the car I about passed out. I had to roll the windows down and freeze all the way to work this morning. That was an hour ago and can still taste the fumes in the back of my throat.

What is going on here? I guess I know why it needed to be idling so fast before, to burn off all this extra gas!

Is this a one time thing, the ECU catching up to the drastic change in idle speed? I thought that it would be smart enough to adjust.

On a probably related note, I did the universal 1-wire conversion of the o2 sensors a few weeks ago. I know that the difference with the 1 wire sensors is that they don't have the built in heater, so they take a while to start working properly... But should it be so bad as to be a safety hazard? Seriously, the inside of the car was like a malatov after running for 10 minutes.

Thanks guys!
James
 

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Discussion Starter · #4 · (Edited)
Here's an update, I drove home just now for lunch (didn't let the car idle and heat up for more than a minute) and didn't smell gas at all.

The car, however, this morning on the way to work, as well as just now at lunch, isn't heating up like it's supposed to. It took almost the whole trip home (and to work this morning) for the temp guage to reach normal operating temperature, just below the half way mark on the guage. The air blowing from the vents is not very warm at all.

Hopefully this new info will help diagnose the problem.

Thanks again and karma for you
James
 

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Discussion Starter · #6 ·
napalm said:
It is your thermostat that needs changing.
Do you think? I have certainly had thermos go bad in cars before... The not heating up properly and blowing fairly cool air out of the heater would support that theory, but in reference to changing the idle speed last night and getting fumed out this morning, is it all related?

It seems unlikely to me, but I don't know, that's why I asked!

Thanks
James
 

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If you're thermostat is stuck open slightly it will take extra time to fully warmup. And, during colder coolant temps your gonna run richer as the ecu supplies more fuel when cold and slowly backs off until warm.

And the O2 sensore could be making your idle high, because at idle they tend to not be warm enough to send the ecu a signal and the ecu will read this as a completely lean condition and run you extra rich. So, you may have a couple problems all in one!
 
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I am rest assured you have a Thermostat problem. I just changed the thermostat on my girlfriends car around a week ago because she had the exact same symptoms as you. As far as the idling is concerned, I do not support the idea of changing the idle speed. RPM's fluctuate for a reason and it is not because of the idle screw. When you start your car in the cold, you should expect around 1500 - 1800 RPM until the car has warmed up and then goes back down to 800 or 750.

Now you also said that when you were at a light, RPM's fluctuated between 1500 - 2000. This is either a vacuum leak or a faulty EGR system. The fumes that you witnessed in the morning is also a possibilty of the Coolant Temp sensor

What we need to determine here is the codes. Try grounding the pins, GND & Ten. Get the codes and reply back. I will be able to help you out some more.

Regards,

mez
 

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Discussion Starter · #9 ·
adjat84th, thanks for the response:

Until last night, after lowering the idle speed, the car warmed up very quickly, blew hot air like it was supposed to, no issues at all.

napalm, thanks again for helping out:
I know that the car idles fast when trying to get warmed up. The problem was only once since I have owned it has it ever idled below, say 1500. Sometimes as high as 2000. The idle was set WAY too fast. I think the screw was about to fall out it was so loose.

In my original message when I said "It wouldn't kick down, but eventually if the car idled long enough, it would drop to just under 1000, where it is supposed to be." I was referring to a situation where we were working on the car, needed to start it up and let it warm completely up without touching it, it dropped down and idled at the right speed.

So, no matter how long I drove it, on a several hour trip, even, the idle would never go down. Only in the above situation where you start it up and don't touch anything for 15 minutes, it dropped down to under 1000.

Anyway, I tightened the idle air screw 8 or 9 full turns to get it down to idling around 1100 w/o accessories and 750 w/ accessories.

After THAT the issue with the gas smell and not heating up very quickly.

I know there is a vacuum leak, or at least that's the symptoms...

On the CEL codes, as stated above, I have only code 16, EGR, which has also been around since I got the car.

Is it possible that any of the above could give the same symptoms as a bad thermostat? It's just strange that all of this came on at the same time.
 

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It seems to me you have more than 1 problem. We need to fix one problem at a time to see what is the real culprit

1) Locate the vacuum leak.

2) After this adjust idle till car specification.

It is very hard to determine what is the problem with the car if a vacuum leak is present. Open the hood of your car and try to hear where it is coming from.

The symptoms mentioned above isnt relative to bad thermostat symptoms.

The faulty EGR however will make the car run rich and therefore not pass emissions. I had the pesky code 16 too. It goes away and comes back after awhile. I plan on cleaning my EGR valve sometine soon. That might get rid of the problem. I suggest however you get the vacuum leak fixed asap. I hate bouncy idles.
 

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Discussion Starter · #11 ·
Good advice!

Thanks, man. My main concern this AM was the gas fumes. It was really an unbelievable amount.

On a side note, the bouncing idle resulting from the vacuum leak has not happened since lowering the idle speed.

When changing my o2 sensors, the second project of the day was going to be removing and cleaning the EGR to try and clear the code 16. We struggled with it, got it disconnected, but not removed (couldn't get the EGR side of the pipe removed) and it was apparent that we weren't going to clean it and get it back together before dark, so we said screw it and put it back on.

I reset the ECU, the 17&24 codes disappeared, then blew wet black carbon chunks out the exhaust (I guess from just *handling* the EGR it knocked some stuff loose in there) and the rolling idle appeared that very day.

I have listened very closely in the engine bay and wiggled some connections to try and make a whistle or at least a discernable sucking sound, but have not yet found the leak. All of my vacuum lines are so very brittle it is really hard to say it could be any one of them.

Thanks again for the attention, Napalm!
James
 

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No Problem James,

Always glad to be some help

mosheen said:
On a side note, the bouncing idle resulting from the vacuum leak has not happened since lowering the idle speed.
You always had a vacuum leak, so by lowering the idle, you found an easy fix to stop the idle. However by doing that, your cars idle will not be the same now due to the existing vacuum leak and hence the prominent causes for excess gas fumes and so on.

I hope you find that damn leak. Do note that once you have the vacuum leak sorted out, your car's idle will be a lot lower and will need to be changed higher.

Regards
 

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You need to get your hands on a vacuum pump and just start goin at each vacuum hose and apply vacuum (with the car off), where it doesn't hold vacuum you've found the leaker.
 

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Discussion Starter · #14 ·
You guys are awesome.

I wonder if the vacuum pump is one of those "loaner tools" you can get from Auto Zone... Hmmmm.

Probably not.

Anyway, I will be looking at it when I have a chance. Unfortunately I have only a driveway, not a garage and limited tools... and it's winter time now... damn.

There will be a warm weekend coming up shortly. I just know it!
 

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Discussion Starter · #16 ·
Here's an update (just for future searching)

My newly installed CAI... The filter cone was jammed all the way up on the down pipe. The inside cup of it is grooved, to allow airflow, but it was definitely up too far.

Anyway, I loosened it, slid the cone about 5" down, tightened it back up and BAM.

Problem solved. It was choking to death.

I had to raise the idle back up about 500 RPMs from where it was. As soon as I moved the filter, the idle dropped way down. So, I haven't had the gas fumes in the car for a couple of days, I don't know if that is related, but it is idling right and the car heats up like it is supposed to.

Still no "rolling idle."

James
 
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