740 Rough Idle when Cold
#1
740 Rough Idle when Cold
Hi I'm Josh, I am new to this forum but definitely not new to being an owner of a Volvo. I've owned my 1992 Volvo 740 wagon for about 5 years now.. now here is my problem.
Recently my car has been giving me some trouble when idling while cold. I'll start with the symptoms and then go into what I have checked so far.
It will start right up when cold but when it goes to idle, it will bounce between about 400-600rpms. It bounces between the two about once every second, which causes a very rough idle that causes the entire care to rock back and forth. Once it warms up, this goes away but there is another problem. If I press on the gas pedal, the revs go up without any hesitation. However, if I barely press on the gas pedal (similar to if you were in traffic and barely pressing on the gas to move up a couple feet) the car drops revs and acts as if it is going to stall but after my foot is removed, the car will return to a normal idle.
A couple months ago I put in a VX camshaft and adjustable cam gear. Had no issues with idle after installation. I live in ohio so it is starting to get colder, especially in the morning. Yesterday I removed my IAC and gave it a thorough cleaning, it looked like it was in good shape though. The connector looked good as well. I also checked the TPS position and it clicks right before the butterfly valve starts to open. I also inspected the Throttle Bottle and it was very, very dirty; maybe this is the issue? I have attached 2 photos.
I appreciate any advice or help on this issue!
Josh
Recently my car has been giving me some trouble when idling while cold. I'll start with the symptoms and then go into what I have checked so far.
It will start right up when cold but when it goes to idle, it will bounce between about 400-600rpms. It bounces between the two about once every second, which causes a very rough idle that causes the entire care to rock back and forth. Once it warms up, this goes away but there is another problem. If I press on the gas pedal, the revs go up without any hesitation. However, if I barely press on the gas pedal (similar to if you were in traffic and barely pressing on the gas to move up a couple feet) the car drops revs and acts as if it is going to stall but after my foot is removed, the car will return to a normal idle.
A couple months ago I put in a VX camshaft and adjustable cam gear. Had no issues with idle after installation. I live in ohio so it is starting to get colder, especially in the morning. Yesterday I removed my IAC and gave it a thorough cleaning, it looked like it was in good shape though. The connector looked good as well. I also checked the TPS position and it clicks right before the butterfly valve starts to open. I also inspected the Throttle Bottle and it was very, very dirty; maybe this is the issue? I have attached 2 photos.
I appreciate any advice or help on this issue!
Josh
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nkinkade
Volvo 240, 740 & 940
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02-28-2014 08:49 PM