Erratic Idle On Cold Start
- Thread starter murdermachine
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Re: Erratic Idle On Cold Start
Installed a new CTS, no luck. It sounds like it wants to rev up to smooth out the idle, but can't. I will swap out the vacuum lines this weekend. Anything else to keep any eye out for? It idles extremely rough until it is fully warmed up. A bit stumped.
Installed a new CTS, no luck. It sounds like it wants to rev up to smooth out the idle, but can't. I will swap out the vacuum lines this weekend. Anything else to keep any eye out for? It idles extremely rough until it is fully warmed up. A bit stumped.
Re: Erratic Idle On Cold Start
I'm pretty sure it is a vacuum line. I did a cold start and as it was running like shit, I started wiggling vacuum lines. The idle kicked up like it should on a cold start and slowly dropped to a steady idle. I have 2 100ft spools of the sizes I need. Hopefully I should be solid after.
I'm pretty sure it is a vacuum line. I did a cold start and as it was running like shit, I started wiggling vacuum lines. The idle kicked up like it should on a cold start and slowly dropped to a steady idle. I have 2 100ft spools of the sizes I need. Hopefully I should be solid after.
Re: Erratic Idle On Cold Start
Replaced vacuum lines. It idles rough on a cold start until the idle kicks up after 30 seconds... After the idle kicks up and slowly settles back down, it runs great. Anything else to check?
Just to recap, Adjusted IAC counts on TB adjustment, cleaned TB and IAC, replaced vacuum lines, replaced CTS.
Any chance it could be the EGR for some reason? I have 3-4 spares sitting around. I am going to swap one just because a person mentioned it in another thread, and it doesn't take long...
Replaced vacuum lines. It idles rough on a cold start until the idle kicks up after 30 seconds... After the idle kicks up and slowly settles back down, it runs great. Anything else to check?
Just to recap, Adjusted IAC counts on TB adjustment, cleaned TB and IAC, replaced vacuum lines, replaced CTS.
Any chance it could be the EGR for some reason? I have 3-4 spares sitting around. I am going to swap one just because a person mentioned it in another thread, and it doesn't take long...
Re: Erratic Idle On Cold Start
Looked in the manual and did some research on the EGR Valve. It is supposed to pretty much stay closed and only opens during closed loop and mainly freeway driving. I started my truck and my EGR valve instantly opened. I pulled off the vacuum line, letting the EGR close, and the idle kicked up like it is supposed to and started running good. I hooked up the vacuum line again and it started running like crap. After it warmed up, the EGR valve closed, like it should have been the whole time.
I don't have time to order parts, so I am going to disconnect the EGR valve so it won't run like crap on a cold start. This should help when I go to ship the truck back to the states. As long as I don't hot rod it around, I shouldn't have any issues... correct?
Other than a CEL, am I better off installed an EGR delete plate I have laying around from my TPI car? Or should I just disconnect it and leave it?
Looked in the manual and did some research on the EGR Valve. It is supposed to pretty much stay closed and only opens during closed loop and mainly freeway driving. I started my truck and my EGR valve instantly opened. I pulled off the vacuum line, letting the EGR close, and the idle kicked up like it is supposed to and started running good. I hooked up the vacuum line again and it started running like crap. After it warmed up, the EGR valve closed, like it should have been the whole time.
I don't have time to order parts, so I am going to disconnect the EGR valve so it won't run like crap on a cold start. This should help when I go to ship the truck back to the states. As long as I don't hot rod it around, I shouldn't have any issues... correct?
Other than a CEL, am I better off installed an EGR delete plate I have laying around from my TPI car? Or should I just disconnect it and leave it?
![Quickstop [UK]](/data/avatars/m/5/5165.jpg?1570199786){kind=avatar}
Quickstop [UK]
Combating adversyty.
Re: Erratic Idle On Cold Start
The delete plate may look good but honestly, I don't think it does much. The channel in the intake is still there with the hot exhaust. You would need to remove the upper intake and plug that port to stop hot gases from warming the intake. I would just disconnect the EGR for how.
It does seem odd that it is coming on erroneously but good job figuring it out. Must run pretty well now!
The delete plate may look good but honestly, I don't think it does much. The channel in the intake is still there with the hot exhaust. You would need to remove the upper intake and plug that port to stop hot gases from warming the intake. I would just disconnect the EGR for how.
It does seem odd that it is coming on erroneously but good job figuring it out. Must run pretty well now!
Quickstop [UK]
Combating adversyty.
Re: Erratic Idle On Cold Start
With the EGR disconnected, there's just as little flow, surely? It's just closed. My impression was that the plates are there for cosmetic reasons and less beneficial than properly plugging the intake (3/8 allen plug after it has been tapped would have been my course of action if I didn't already have a plate).
I'm particularly averse to the plate because of the stupid designs that I have seen... The meat of the plate is milled out by RPM and others so it is easy to install it the wrong way round and inadvertently leave the EGR open all the time. I have one of SY2932 (Mike Campbell's) which is flush on both sides and looks damn good whilst also preventing incorrect installatiion.
Granted, limited flow means limited heat transfer but in this world where people seem to want every miniscule gain imaginable, plugging it is better than a plate.
With the EGR disconnected, there's just as little flow, surely? It's just closed. My impression was that the plates are there for cosmetic reasons and less beneficial than properly plugging the intake (3/8 allen plug after it has been tapped would have been my course of action if I didn't already have a plate).
I'm particularly averse to the plate because of the stupid designs that I have seen... The meat of the plate is milled out by RPM and others so it is easy to install it the wrong way round and inadvertently leave the EGR open all the time. I have one of SY2932 (Mike Campbell's) which is flush on both sides and looks damn good whilst also preventing incorrect installatiion.
Granted, limited flow means limited heat transfer but in this world where people seem to want every miniscule gain imaginable, plugging it is better than a plate.