jc in rb

hey guys, been have'ing a bit of a prob lately will what "feels" like overboost protection.Car runs great off boost and for about 5-10 seconds at full throttle, then it hits a wall that feels just like overboost protection. I have checked my boost build and tapper of with the stock guage and it does build and then tapper off(does not max the guage out)so it seems the cyclic valve is working?If i try this in 3-4-5th gear the car just shuts down till i back out of the throttle then will sometimes stall.Car is stock chip ,dme never been opened. I did have a boost enhancer on it for a while but it would over boost all the time if i rev'ed it out , so i removed it.So where should i start looking (klr-dme-coil-??)Its realy bummin me out since i just got my suspension and brakes sorted out and would love to be out driving..butt nooooo

jlturpin

Does it happen at a specific RPM? You need to check fuel pressure, and make sure the FPR has a good signal (vacuum lines). You could also check plugs and plug gap. Also check boost hose between Turbo outlet and hard pipe, had one rip on the underside and it caused similar problem, too much fuel.

jc in rb

When it first started it was at about 5600 rpm then yesterday it happened at 4000 rpm under load.What should my fuel pressure be.Sounds like that may be it......?fuel pump going bad....?

bw993

Sounds like you have a leak in your intake, after the AFM/MAF that is causing the car to run rich under load. This will cause your car to cut out until you ease off the thottle.

jc in rb

"Sounds like you have a leak in your intake, after the AFM/MAF that is causing the car to run rich under load. This will cause your car to cut out until you ease off the thottle" hummmm ,i think you may have something there. I just found a disconected vac line that runs along the back of the firewall and an un-used vac line receptor under the back of the intake ,right behind the cyclic valve can feel any vac on it but i can sorta hear vac somewhereAlso my car has been eating gas like crazy.had the shop check a/f ratio's and they said it was all in spec but that was just static no load/boost ......

jc in rb

Problem solved,thanks bw993. could'nt feel any vac on that little what ever it it under the intake behind the cyclic valve (looks heater related) but hooked the loose vac line to it and the car runs perfect now!

Shawn Stanford

Same symptom, same problem, same solution. Thanks Rennlist!