Hi :)

[gmcyukondriver]

Right now we're trying to narrow down an idle issue while the truck is in drive. We've gone through almost everything and we're unsuccessful as of now. So hopefully that gets straightened out soon so it doesn't have to be put into neutral at red lights.

What is it doing, specifically? My main guesses would be the IAC valve, TPS sensor, or the throttle body gasket. Those will tend to mess with it when you're stopped, but not when driving.

 

[RHamill]

I like Brandons 81 Monte, reminds me of the old 87' G Body Grand Prix I used to have.

 

[Swaggerwagon]

oh hai........

 

[MonteCarloChick]

I like Brandons 81 Monte, reminds me of the old 87' G Body Grand Prix I used to have.

'85

What is it doing, specifically? My main guesses would be the IAC valve, TPS sensor, or the throttle body gasket. Those will tend to mess with it when you're stopped, but not when driving.

And the truck will drop and flutter RPM's in drive and stall. It'll be fine in neutral and while driving, but when the truck is stopped, it has the issues. TPS is the next thing to check out. We looked for vacuum leaks but couldn't find any. We checked timing and it was fine also. Fuel issues were ruled out. It's been a headache for months now.

 

[RHamill]

'85

Ahh really? I thought that was a 1 year only grill. I guess I'm so used to seeing this style

You must be registered for see images

That style must be the SS, and the style your BF has is the non SS I take it.

I like this style the best here.. 78-80

You must be registered for see images

 

[Toms94z71]

'85



And the truck will drop and flutter RPM's in drive and stall. It'll be fine in neutral and while driving, but when the truck is stopped, it has the issues. TPS is the next thing to check out. We looked for vacuum leaks but couldn't find any. We checked timing and it was fine also. Fuel issues were ruled out. It's been a headache for months now.

When my truck was doing that recently it was the IAC the plunger spun itself out and it would stall randomly at lights or if i had my foot of the gas going thru a turn it would sometimes.

 

[Tempted]

Yeah I'm gonna say IAC, then MAP, then vacuum, then injectors. Most TPS issues are present at a driving speed, it isn't real common to get one that makes a truck bog/stall at idle. If the IAC checks out fine try running a half bottle of Sea Foam through the brake vacuum line. Let the truck warm up to operating temp, feed in about half the bottle through the line, shut the truck off and let it sit for a few minutes to steam out, then crank her up and clear her out. Gonna smoke like a train and run like a Yugo for a few minutes, but it'll clear up. The dealership calls this a "top end treatment" and charges about $150. When I was at the Lincoln dealership we had a special Motorcraft bottle of the stuff at about 3 times the price but identical in make up and size.

 

[Aloicious]

sounds kinda like a stuck open EGR valve too

 

[MonteCarloChick]

Ahh really? I thought that was a 1 year only grill.

Yeah, it's an SC (Sport Coupe). And I also love the 3rd Gens as well. You rarely see them anymore. At least around here.



And we did the IAC valve, MAP sensor, cleaned out all the EGR parts, checked the fuel system (injectors, pump, etc.). Nothing has made a difference The truck won't present the problem all the time either. The next thing on our list of things to check is the coolant sensor as suggested by someone else.

 

[BlackBeauty]

Welcome and sweet rides!!!