Cam95Maro

iTrader: (1)

Okay guys car sat for a while while installing new rear and new stall and new suspension components hers my issues.


This has been doing it for a while but sitting at idle rpms move up and down up and down also when going up a hill or any slightacceleration under load the rpms go up and down up and down like it's pulsating.
At idle it's not bad but under load it's very very noticeable

Secondly I put a rear in the car a strange s60 with 4.11 gear and a vigilante 3200 stall at wide open throttle it will not shift 1-2 or 2-3 I have no check engine lights or anything also know it is NOT TUNED yet as I had to do the break in mileage for rear before heavy acceleration. My question here is will the tune take that away or is something else going wrong?

Other things to know pretty much stock car have pacesetter long tubes slp loudmouth 2 exist slp cai and I did put a trans cooler in... trans has plentyfluid checked it three times all good there and trans was built less than 5k miles ago

Thanks for the help or suggestions ahead of time.

rjmarazzi

iTrader: (1)

I would say that a tune will fix the shift problem not sure on the surging problem. May be some one else can explain more as to why but I do no with 94 and up with 4l60e when you put a stall in it needs a tune. But not on the 93 4l60.

Jeff400w

We had the same issues shifting, we were able to fix them by tuning. Does it surge when it's cold or only warm? Have you checked for a vacuum leak?

Cam95Maro

iTrader: (1)

It surges cold and warm I will start looking for a vacuum leak

Cam95Maro

iTrader: (1)

Could the crank case vent hose being cracked cause a unstable idle and a surging under load? I found that today. Also, the vacuum hose that would normally go into the stock intake is just sitting in the engine bay could that cause a problem? Also, was looking around could the PCV valve have anything to do with the pulsating ? Just asking quesitons before i throw money at it.

Corvett z07

iTrader: (2)

The crank case vent hose and PCV valve would most likely not be the culprit here, however I would replace the crank case vent hose since it's cracked, they're relatively "cheap insurance" for your car in the long run. My crank case vent hose was just unplugged when I bought my car, I plugged it back in and nothing changed to my discernment. I replaced my PCV valve when I did a tune-up, again they're cheap and considered part of a regular tune-up, but shouldn't cause a surge in idle unless it's completely plugged. As far as the vacuum vent hose, I'm not familiar with that exactly, someone else can shed light onto that, it's there for a reason