Car won't rev over 2K-intermittent prob.

[GNSteve]

I need help. Again.
My car has a problem that only happens when it's warmed up, or at full operating temperature. When the problem occurs, I cannot give the car more than 1/4 throttle. If I do, the engine immediately cuts out. Nada. Nothing. If I back off quickly, the engine sometimes resumes running. Otherwise, it dies. However, I still have battery power going to the radio, lights, etc...
I *thought* this problem was due to a bad ignition module or coil. I replaced both recently, ensured proper grounding, and the problem still occurs. Like I said earlier, the problem is NOT consistent. It seems to occur only when warm, and always at the same position on the throttle.
The ECM is not showing any codes. I "tap tested" my LT1 MAF and it seems OK. I'm thinking that it could possibly be my TPS, ECM, or maybe a strange grounding problem.
Could anyone give me some more possibilities on what the problem might be? Thanks!

 

[REDS HOT AIR]

hang ya a fuel pressure guage on it and see what it does when it acts up

maybe faulty pump that acts up from time to time or relay not sending healthy voltage at times

has the pump been upgraded?and the stock colapsing sock on it changed?

 

[VIN7]

Do you have Direct Scan?

Mike

 

[GNSteve]

REDS,

I upgraded my pump a while back to a Walbro 307 with hotwire. This included new upgraded sock, etc...
I think you may be on to something here. I discovered this morning that the relay wire to the hotwire was close to the DS header. It melted the looming around the wire, but not the wire itself. This *might* be the culprit.
I was under the impression that the hotwire kit was designed to revert back to the "stock" setup if it failed, thereby keeping fuel flowing to the engine. What do you think? True?
Anyhow, I'm going to recheck the condition of the wire, and re-route it away from the heat. Hopefully this will take care of it.

Mike,

No Direct Scan. I'm using a Scan2. Anything in particular you think I should check? Thanks!

Anyone else got any ideas? Please?

 

[GNSteve]

Anyone else have ideas? Please?

 

[Quick6'n'-K.C.]

my 85 would do the same thing, it has the 86/87 engine in it-

first i thought it was the chips going bad, because one day i changed the chip, and the car ran flawlessly- turned out not to be that-

then i noticed my passenger side headlights were dim as heck, and the car wouldnt rev up past 2 k like you said-
it was weird, sometimes it wouldnt do it, sometimes it would, i even thought it was the MAF cause when i went to blip the throttle, it would backfire like the cam sensor was out of wack! but i knew it wasnt cause i just installed the engine a few months back-

i cleaned up the ground wire at the battery, and it goes down to underneath the turbo, and bolts to the head, clean those up and see what it does-
check to see if the positive cable is not being hit on the downpipe going to the starter-

check the ground to the passenger fender, its a 10 MM headed bolt and it grounds right next to the battery- just unhook them and clean off the surfaces for a good contact-

does the ses light ever flicker on and off super fast?
if so, check the prongs on the computer where the chip seats..

let me know what you find, i try to help ya out as best as possible-
LAST thing to check, maybe your gas gauge is off and your low on fuel, the car can idle but not rev up,... ive done that a time or too!
BW

 

[1badTTA]

Also check the TPS, had a car (not a TR) with a bad one, same thing would happen when it got hot, buck and stumble over 1/4 throttle. HTH

 

[LeesGN]

You should know better than to try and rev a pushrod motor over 2k. It just WONT rev any higher.