my 86 t just wont run right. the last time i was at the track during my burnout it started popping and cutting out. i left the line at 2# and it pulled strong until it got up in the rpms at wot, popping and cutting out. let out and get back in same thing all the way down the track.times were as follows: 60' 1.75, 1/8 7.71@90mph, 1/4 12.04@113mph. fuel pressure was set at 40# with vaccum line off, C16 fuel@20# boost. the car has several mods. 50# injectors, rjc plate, regulator, te44, pte front mount, ls1 maf, translator, i think it has reds chip(three different ones), scanmaster, and bstc boost controller. there was no detonation on the pass, and the o2 read around 740. i feel like the car can be much faster im just needing some help and guidance. all suggestions and help would be greatly appreciated!!!
popping/cutting out
- Thread starter wes1124
- Start date
DailyDrifter
The Slow and the Curious
- Joined
- Dec 5, 2007
How olds the fuel pump, and is it a defective Walbro? Has the fuel filter been changed? Is it popping out the intake? What o2's are you seeing when the problem occurs? I would also bump the fuel psi up 2-3 more lbs.
DailyDrifter
The Slow and the Curious
- Joined
- Dec 5, 2007
If its coming out the exhaust its rich. What are your plugs gapped at? Fuel psi should raise 1:1 so if you are running 15psi with a baseline of 40lbs you should end up with 55lbs of fuel at WOT.
DailyDrifter
The Slow and the Curious
- Joined
- Dec 5, 2007
After you run the car ohm out the coil pack. It could be weak.
- Joined
- Feb 18, 2006
Try swapping the cam sensor cap from your buddies car. If that does not help, replace your crank sensor with a new ac delco one. Make sure you set it up right. Rotate the crank and check clearance on all three blades that pass through the sensor. Make sure the wheel is not bent.
GL
GL
darkred87T
Active Member
- Joined
- Oct 27, 2003
subscribed
I have the same problem. I swapped coil pack/module (with another old one), bought a new cam sensor cap, swapped injectors, plugs, and monitored FP. My plugs look normal; maybe a little lean. FP is steady. Have you tried replacing the plugs?
Also, it is not only WOT. It also happens under part throttle. It has a stumble at idle. Sound familiar?
Keep us posted. Thanks,
Mike
I have the same problem. I swapped coil pack/module (with another old one), bought a new cam sensor cap, swapped injectors, plugs, and monitored FP. My plugs look normal; maybe a little lean. FP is steady. Have you tried replacing the plugs?
Also, it is not only WOT. It also happens under part throttle. It has a stumble at idle. Sound familiar?
Keep us posted. Thanks,
Mike
I subscribe! My only seems to occur at highway speeds and under partial throttle and if I don't let off the throttle, it will stall.
I did see a dip in the fuel pressure, only a little 5 or 6 psi. It was not dropping out completely.
I have another ECM that I'm going to try and go from there.
If you guys come up with anything else, please post it.
Thx,
Charles
popping cutting out
I had the same problem about two months ago at first I thought it was the coil pack also,so I replaced it but it still was cutting out or busting up on top so after talking to several GN experts we found out it was a weak valve spring if youre running those comp bee-hive springs that may be the problem I changed springs and its not busting up no more.
I had the same problem about two months ago at first I thought it was the coil pack also,so I replaced it but it still was cutting out or busting up on top so after talking to several GN experts we found out it was a weak valve spring if youre running those comp bee-hive springs that may be the problem I changed springs and its not busting up no more.
that national
Member
- Joined
- Mar 3, 2006
try checking all of your grounds. its worth a try
follow_me_22
New Member
- Joined
- Sep 14, 2001
ttt
Let me chime in here... I basically am getting the stumble off idle/ 20% throttle and an occasional popping/ backfire, step into a little more and it goes away. Car runs a little rough at idle and it does it when the car has ran for a while. I had coil pack tested, was good. changed fp with hotwire kit, filters and fp regulator 42 line-off and a cold air kit. my fuel pressure was way high before @ about 47-49 line off before i changed to adjustable.......
...UPDATE LoL..
While I was typing this I stopped and went to open my hood for some reason, did a quick glance check and noticed crack on the vac lines to the vac block on top of throttle body. A quick search and i found a hose in better shape, swapped it out and felt an immediate difference. I dont know if the occasional stumble is cured but the idle, quick test drive showed much improvement. I just bought a few feet of hoses and will change anything looking suspect and report back.
Let me chime in here... I basically am getting the stumble off idle/ 20% throttle and an occasional popping/ backfire, step into a little more and it goes away. Car runs a little rough at idle and it does it when the car has ran for a while. I had coil pack tested, was good. changed fp with hotwire kit, filters and fp regulator 42 line-off and a cold air kit. my fuel pressure was way high before @ about 47-49 line off before i changed to adjustable.......
...UPDATE LoL..
While I was typing this I stopped and went to open my hood for some reason, did a quick glance check and noticed crack on the vac lines to the vac block on top of throttle body. A quick search and i found a hose in better shape, swapped it out and felt an immediate difference. I dont know if the occasional stumble is cured but the idle, quick test drive showed much improvement. I just bought a few feet of hoses and will change anything looking suspect and report back.
darkred87T
Active Member
- Joined
- Oct 27, 2003
Good theory though Iv'e pulled my hair out looking for vacuum leaks, lol. My vac tree and hoses are all new as well as a new intake gasket and EGR bypassed. Pressure tested the intake, ect..... but not my thread so.:redface:
follow_me_22
New Member
- Joined
- Sep 14, 2001
ttt
No luck... still off idle/20% throttle stumble. It only happens after the car runs and turns off a few times.. A buddy of mine said it could be the maf sensor. It is stock and you never know, so tomorrow I'm ordering a gen2, ls1 and 4" piping. Hopefully this will take care of it. I hate throwing parts at the car to solve a mystery.
Sorry for hijacking your thread:biggrin:
No luck... still off idle/20% throttle stumble. It only happens after the car runs and turns off a few times.. A buddy of mine said it could be the maf sensor. It is stock and you never know, so tomorrow I'm ordering a gen2, ls1 and 4" piping. Hopefully this will take care of it. I hate throwing parts at the car to solve a mystery. Sorry for hijacking your thread:biggrin:
popping and cutting out
I put the regular comp-springs in 1-460 im running a 218-212 roller cam and my seat psi is 140, but if youre running a flat tappet you're psi shouldn't go over 100 psi on the seat Im tied up right now but if you want I can get the part # later and shoot it back to you if you dont get the problem fixed.
I put the regular comp-springs in 1-460 im running a 218-212 roller cam and my seat psi is 140, but if youre running a flat tappet you're psi shouldn't go over 100 psi on the seat Im tied up right now but if you want I can get the part # later and shoot it back to you if you dont get the problem fixed.
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