Skip/Miss at Light Throttle.

[HighMileage]

I keep having these skip/miss issues. This time it's at very light throttle and deceleration. On decel, an occasional *pop* is heard from the exhaust.

Once past light throttle pressure,the engine pulls smoothly and strongly. WOT peels me eyelids back! Idle is *ok*.

Cruising along with the TCC engaged in 3rd is when it is really noticeable. Like a bucking bull.

Other skip/surge issues have been solved by:
1)New coil pack.
2)Check/replace vacuum lines. There are no leaks now.
3)The TPS is set perfectly with no dead spots.
4)New,correct PCV.
5)New,correct plugs gapped at .030 per TurboBuRick.
6)Fuel Press 43 with line on,55 with line off.

Note: When I replaced the old fuel filter a few weeks ago,there was a piece of cellophane stuck in the outlet of the old filter.

Any input appreciated.

Steve. '87 GN. Mostly stock. Powerlogger. <--still reading about how to correctly use that.

 

[TurboBuRick]

Steve,

Why is the fuel pressure so high?

Still running the original crank sensor?

 

[pajo]

?

x2

 

[turbo nasty]

x3 on teh fuel psi I bet your blm's are way up

 

[HighMileage]

x3 on teh fuel psi I bet your blm's are way up

BLM's are 129 at idle with a checkmark in the BLM Learning box.

I also did notice that the PL shows .36v at idle. It showed higher a few weeks ago when I checked it with my vom. I also have a 7.36 AFR.

Rick: The crank sensor appears original. It doesn't show that it is rubbing on the balancer. I haven't touched it.

As far as the FP of 55 with vac line off. No idea. It is the factory reg.

It runs great. But has definate light throttle issues.

Not sure where to start with this one. Been fixing things right along here with much success.

Steve. '87 GN. Mostly stock. Powerlogger.

 

[GottaBuick]

Subscribed, are you still running the stock pump along with your factory FP regulator? Just interested in what you combo is, I have always had the same problem with my car since I had it. Just a little miss/stumble under cruise with TC locked in higher gears, but runs WOT and at idle like a champ.

 

[TurboDave]

What chip are you running???

Could you by chance have lean cruise enabled????

If you're running that much fuel pressure with the stock regulator, I would highly suspect the accuracy of your gauge!!!!!!!!!!

 

[HighMileage]

Stock pump,stock chip,stock regulator. I'm gonna adjust the TPS up a little and see what happens.

As far as the FP tester I have. It is a new one from Sears. Not that it means anything.

Soon I'll be getting an Autometer FP gauge,and I'll compare. Maybe it will arrive today. ?

Steve. '87 GN. Mostly stock. Powerlogger.

 

[HighMileage]

Subscribed, are you still running the stock pump along with your factory FP regulator? Just interested in what you combo is, I have always had the same problem with my car since I had it. Just a little miss/stumble under cruise with TC locked in higher gears, but runs WOT and at idle like a champ.

I adjusted the TPS up to .44v from .36. No change. Not that there was supposed to be.

The car does not like light loads under 1,600rpm. Once the TCC engages in 3rd,the bucking bull comes back to where there is occasional drivetrain slap. You know,this wasn't so noticeable a few weeks ago before I fixed the no TCC issue! lol

***Update on Fuel Pressure: My Autometer gauge arrived today. That new Sears FP tester is reading 10psi over. The Autometer sez 32psi vac line on...42 vac line off.

Maybe that skip/buck under 1,600 is just some generic thing. Not sure what I'll do about it next.

Steve. '87 GN,t-tops. Mostly stock. Powerlogger. No chip,upgrade pump,etc.

 

[buickruss]

How did you get the FP so high with the Factory regulator?

 

[HighMileage]

How did you get the FP so high with the Factory regulator?

That brand new FP tester that I bought in Sears no too long ago was reading 10psi too high according to a new Autometer 2 5/8 liquid filled gauge in the mail today. Reads 32psi with line on,42 with vac line off.

I believe that is what the FP is supposed to be. Stock pump,stock FP reg that sez Bosch on it.