Won`t go over 65mph?

[steveX]

I have a 86 GN, which came from a auto-repair shop after the long block (engine) was replace (long storie). Anyway i got the car runing and drive nice . The car was in a mess when i got it, so i had to replace all the vacume line with check-valve. after test drive the car i found a bad wastegate actuator. The boost gauge will go 20+psi at WOT. i replace the actuator and boost is at 12psi (set). I still have to look over the auto-repair work. NO SES light. while driving at 65mph the trans will feel like it disconnect from the driveline (ONLY AT 65) once the speed fall below 65mph i feel the trans connect, and then i can drive to 65mph. then repeat. When the car does hit 65mph i can rev the engine but the power is not tranfer to the wheel to contiune pass 65mph. Any idea?

the owner currently have the car, and is driving around with it. He told me some time the car will go pass 65mph I never experance this when test drive car. so most of the time the car will not go pass 65mph. Car never had this problem before the engine rebuild.



thank you

 

[notacarlo]

Might be some type of anti-theft or parental feature of the prom chip.

 

[steveX]

I was thinking the same thing, but when the owner told me the car never had this problem before, and sometime the car will go over 65mph now. I will be looking at the car today.

 

[Blazer406]

Are you saying the car performs great up to 65 mph.... just like it should for the mods and boost level?

That is real odd.

Wonder if the tranny is staying in second? like high gear comes and goes?

 

[waddell87]

Might be some type of anti-theft or parental feature of the prom chip.

Maybe try resetting the computer. unplug your orange computer wire by battery, Might be something simple like that; you always hope, then try again

Strange though,

 

[SouthernCal GN]

Take off the parking brake

 

[ChrisCairns]

I once had a Toyota that wouldn't go over about 60. Turned out to be a plugged catalytic converter.

 

[waddell87]

Take off the parking brake

SouthernCal you changed your Avatar...

LOL Why didn't I think of that, Parking Brake. Once I couldn't think of why the H**l all the smoke out the rear of my truck..Yup..parking brake.. LOL.Thanks for making me relive that you wiener.:biggrin:

 

[turbofrank]

tps

 

[SouthernCal GN]

SouthernCal you changed your Avatar...

LOL Why didn't I think of that, Parking Brake. Once I couldn't think of why the H**l all the smoke out the rear of my truck..Yup..parking brake.. LOL.Thanks for making me relive that you wiener.:biggrin:

Family was watching "Mars Attacks" the other night......and the rest is history!


Bad memories are a specialty of mine- you're more than welcome!

 

[87NAT]

Did you check your tranny fluid?

 

[waddell87]

Family was watching "Mars Attacks" the other night......and the rest is history!


Bad memories are a specialty of mine- you're more than welcome!

Bugs Bunny and the Martian is what it reminds me of, It was my Fav way back when..LOL

Any updates SteveX?

 

[SouthernCal GN]

Bugs Bunny and the Martian is what it reminds me of, It was my Fav way back when..LOL

Any updates SteveX?

Changed it just for you!

AK AK AK................

 

[steveX]

Some much for all the help here.
At lease i am NOT PAY to fix my car.......LOL

I replecae the MAF sensor and now the car goes pass 65mph (thanks to steveX), now i am seeing NO-boost, when i wot the boost gauge will show 2" of vacume, with NO boost. car drives and run/idle nice..

I am think, maybe the ecm is retarting the timing?. i check all vacume line and piping contection o.k.. The car idle perfect(park and drive) at 800 rpm, so the intake system is seal. coil pack is good, EST module is good, I will test the CPS tommorow.

Would a 85 mass air flow sensor work with the 87 ecm? Thanks for any knowageable help.

 

[Blazer406]

unhook your wastegate rod.. and make sure the puck swings freely.... sounds like it might be stuck open.....or you have a huge boost leak somewhere? Check all intercooler hoses and clamps on the pressure side of the turbo....

 

[steveX]

unhook your wastegate rod.. and make sure the puck swings freely.... sounds like it might be stuck open.....or you have a huge boost leak somewhere? Check all intercooler hoses and clamps on the pressure side of the turbo....

I did check the wastegate door and it was jam shut (stuck).This will causing the car boost to go pass 20+psi. Now that the door is fix and i replace the 87 maf with a 85 maf (i had in the garage) .I also check the wastegate actuator for any internal leaks. I can`t find a vacume leak. the car idle perfect and dive with the 85 maf (better than the 87 unit, cause it bad). If i did have a boost leak, this would cause the engine to idle incorrect. I did get a code 42 (EST module). The module is working fine. i am think the code might be cause by the CPS.

I am happy with the car so far, cause it runing better and it is driveable in the busy NYC street. car does not shut-off or give off any code.
thank you
for the help, i will update.

going to watch some bugs-bunny cartoon now

 

[steveX]

SouthernCal you changed your Avatar...

LOL Why didn't I think of that, Parking Brake. Once I couldn't think of why the H**l all the smoke out the rear of my truck..Yup..parking brake.. LOL.Thanks for making me relive that you wiener.:biggrin:

YOU ARE ONE DUMB FUNKER....Have you try sitting on you finger?....an see if it tast like chocolate....LOL. Go make some kids so we can send the to great white war, dumb FUNK.:biggrin:

 

[waddell87]

YOU ARE ONE DUMB FUNKER....Have you try sitting on you finger?....an see if it tast like chocolate....LOL. Go make some kids so we can send the to great white war, dumb FUNK.:biggrin:

At Least Dumb Funker's car works like a dream:wink:

 

[steveX]

I found my boost problem. The turbo shaft snap in half separating the turbine fan from the compressor fan, plus the compressor fan keep getting stuck to the compressor housing...Car runs great, No ses light, drive very nice, with no boost.


I now i am looking to buy a NEW turbocharger. I will invest the one of jack cotton up-grade turbo. I will post picture of the destuction.

I just love how easy these are are to fix...thank goodness

this is the bad boy....