02 suburban 5.3 lopes on cold start

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

NvrMnd85

TYF Newbie
Joined
Nov 19, 2016
Posts
29
Reaction score
8
Ok if i don't drive the truck for a day or 2 itll lope on cold start for a few, sounds like it has a nice cam in it. I run it on e85 and im sure its part of that. Just curious what it is. Im assuming its the computer being grumpy. And as long as its not hirtihu anything ill just leave it.
 

Scottydoggs

Full Access Member
Joined
Dec 16, 2017
Posts
2,522
Reaction score
3,673
Location
NJ
id guess you have a huge vacuum leak. you can check the long term fuel trims, if they are pos +16 its a vac leak for sure.
 
OP
OP
N

NvrMnd85

TYF Newbie
Joined
Nov 19, 2016
Posts
29
Reaction score
8
It only does it on cold start up after its been sitting for a day or two, which doesn't happen much. It only does it on e85 also and ive only noticed it in the middle of a hot day.


Ill try to get video next time it does it.

I figure its something in the tuning caise it smooths out and runs great and it wont do it again on cold start up till the next time i don't drive it for a day.
 
OP
OP
N

NvrMnd85

TYF Newbie
Joined
Nov 19, 2016
Posts
29
Reaction score
8
This was yesterday when it was 90°f out. Engine was at cold temp when started. It does do it nore commonly in winter but its nowhere near are harsh a lope as it did yesterday.

I think its just the computer being slow on adjusting timing and fuel trims. Just didn't know if anyone had had this before.
 

Forum statistics

Threads
129,234
Posts
1,812,534
Members
92,333
Latest member
BWASTEEZE
Top