Surge
 

Hey guys,


My problem is this, Im getting a surge during driving on occasion. Mods are in the sig. Now it seems like this is only happining when it get really cold out, now i live in buffalo, ny, so the temps can get quite cold. I did not notice it all summer after i installed the tune. Now do you guys have any input on why, or what could be causing this. It seems like the rpms will surge up about 500 or so rmps for a second then go back to normal. TIA

More info would be needed about the truck and the mods done to it. I will say that when I had mine tuned at first that it would surge ever so slightly. The truck was running pig rich, we leaned it up a little bit and that got rid of the slight surge that I was having. Although in my previous truck after the cam swap, I was having a pretty good surge issue and we never did get it figured out.

Yeah true that, I just dont have a clue man, i think its in the tune but we have no one up here with a dyno tune so its a PIA But thanks for the insight.

Does it happen at idle? Maybe the IAC valve is sticking or starting to take a poop? You could try cleaning the throttle body to see if that helps.

Im thinking that since its only started since it got cold youve got a leak in your intake some where, try spraying ether (starting fluid) around your throtle body, intake manfold and anywhere you have clamps in your intake. If the motor revs up youve found your leak, also you might have cracked a vaccume line somwhere. Prolly need to check them too.

From yor Sig. TB Bypass -- that's why it does it only when it's cold.

are you letting the truck warm up? i feel like the truck runs better if i let it warm up for 10 mins before i leave every morning. I know you should still be able to start it up and go w/o problems.. but its a 99, its getting old ya know?

Undo the TB bypass, I had some weird shit going on in the beginning of winter too and put my TB back to stock.
The TB bypass is worthless IMO.
2hp at peak.....at best?? Not worth it in our cold climates.

Thank you guys, im going to try putting the tb back to normal, and see if that will cure it. It didnt do it all summer long just when it gets cold out. Yeah it does it even when its warm Slow 4.8 I know she is getting old isnt it amazing how only a few years on a vehicle and it goes down hill.