Darn EGR!!!

[OldSch88L]

With the extreme cold we've been getting the last week, I noticed that my 2.5 was having a hard time starting and stay running. According to the REM, the EGR is always on when I'm having trouble, leaning out the engine. If I don't give it some gas, it runs rough, the idle goes down and stalls on me. On the rare times the EGR is off on start-up, it starts and runs great, has a high idle and rich mixture that settles once the engine warms up. What conditions must be met to trigger the EGR? Also, once at operating temperature, I noticed the idle getting just a bit rougher when the EGR kicks in, with a hint of a hot oil smell everytime. Any ideas?

[eaglescout526]

So it sounds like the EGR is getting stuck open when it shouldn’t be at all. Normal idle, EGR should be off and idle should be smooth. EGR on, idle will be rough. You can always test this idea yourself by pushing up on the EGR diaphragm at idle. The EGR is controlled by a solenoid that’s be the charcoal canister on the passenger side fender. 

[OldSch88L]

1 hour ago, eaglescout526 said:

So it sounds like the EGR is getting stuck open when it shouldn’t be at all. Normal idle, EGR should be off and idle should be smooth. EGR on, idle will be rough. You can always test this idea yourself by pushing up on the EGR diaphragm at idle. The EGR is controlled by a solenoid that’s be the charcoal canister on the passenger side fender. 

But the weird thing is, once warmed up the EGR turns on and off as it should...😞

[eaglescout526]

That makes me think that there’s something sticky in the EGR causing it to stick open until it warms up. If you get a morning where it starts up fine, try to open the EGR manually and see if it sticks. If it does then we can suspect a sticky EGR or the solenoid is failing. 

[cruiser54]

Nothing a BB in the vacuum line wouldn't fix........