Part Throttle Dies

[matt921]

Ok so I am having the weirdest thing happen. I have always had a odd stumble if I stab the pedal in park or drive. It will kinda hesitate then clean out. So yesterday I swapped my fuel pressure regulator cause my old one was crushed and had close to 50 psi at idle. So after I did this swap and now its worse to the point that if I stab it and and hold it 1/2 throttle it will die. I'm at 43psi unplugged and 38 vacuum. But if I stab it wide and hold it it will fight through the spot but still falls on its face then clears. I had got my 87 ecm in the mail and figured well I'm in there. So I swapped it out did the iat and chip swap and a NOS AC DELCO MAF. It ran a million times better idle was smoother boosted faster. But still has the dead spot. I was thinking my tps so I unplugged it and bamn it was gone reved clean and strong. I did throw a check light but it ran great. SO I swapped my tps for a good one that I tested and was a nice clean sweep of voltage. .43-4.53 wide. But still did the same thing. Any one have any thoughts

 

[BRAD_PADGETT]

What is your IAC setting at warmed up in park?

 

[matt921]

25_30

 

[BRAD_PADGETT]

Put your modifications in your signature. What MAF? GM has not made ours in years. What scan tool?

 

[matt921]

It's a nos gm maf. I have the box right in front of me. With the sticker from the dealer. I got it from my buddy who has a bunch of 86 87 parts he got when he bought his car. I am using a snap on scan master.mods are 87 module coil computer and iat. 87 turbo modified for hot air. Srock engine and stock chip. I know it's not that cause this problem started before my ecm swap

 

[matt921]

I think I found it with the scan tool I would wriggle the writes on the tps. Voltage would go to zero then back

 

[BRAD_PADGETT]

It's a nos gm maf. I have the box right in front of me. With the sticker from the dealer. I got it from my buddy who has a bunch of 86 87 parts he got when he bought his car. I am using a snap on scan master.mods are 87 module coil computer and iat. 87 turbo modified for hot air. Srock engine and stock chip. I know it's not that cause this problem started before my ecm swap

This is where a powerlogger is worth the money. I was never able to diagnose anything with a scanmaster with your type of problem. Someone else needs to chime in.

 

[matt921]

That's my next purchase.that's why I went to the 87 computer

 

[BRAD_PADGETT]

That's my next purchase.that's why I went to the 87 computer

Do not beat on your car until you get a powerlogger. Best money I ever spent on my car. The whole buick world opens up when you send them logs. Brad

 

[matt921]

Yeah same thing.if I unplug the tps it will rev clean and boost till shift. But as soon as it is plugged in part throttle on a quick stab it will try and die.but if I slowly ease into it it's smooth.