Help! Car Won't Go Past 5000rpm

[Jordanbutter]

At WOT the car will not go past 5000rpm! The exhaust pops a little bit and boggs down really bad, the boost holds at 10lbs, oil pressure is at 80psi (it has been really low in idle i.e. 5psi) and the O2 volts are .94 drops to .91 occasionally for a millisecond and comes back. (keep in mind this is monitored with the blue wire mod). I did a boost leak test and found nothing. I did try to take out the fuel filter a while back but it whould not budge but if maybe the bottom bolt came a bit loose would this cause a problem?

 

[SBR Joe]

At WOT the car will not go past 5000rpm! The exhaust pops a little bit and boggs down really bad, the boost holds at 10lbs, oil pressure is at 80psi (it has been really low in idle i.e. 5psi) and the O2 volts are .94 drops to .91 occasionally for a millisecond and comes back. (keep in mind this is monitored with the blue wire mod). I did a boost leak test and found nothing. I did try to take out the fuel filter a while back but it whould not budge but if maybe the bottom bolt came a bit loose would this cause a problem?

Check your base timing. I have seen DSM's that had skipped teeth on the timing belt, not enough to bend valves obviously, but was doing the exact same thing you are describing. Does it rev really slow up to 5k and just stop at a free rev?

Joe
SBR

 

[black91awdturbo]

also unplug your mass air flow sensor and see what happens it sounds to me like that is the culprit here.

 

[Jordanbutter]

No it revs pretty fine and it just got a new timing belt a month ago and no it doesn't just stop but it hardly goes anymore.

 

[black91awdturbo]

like I said unplug your mass and try it I have seen more than a few dead mass air sensors and that do what you describe.

 

[Jordanbutter]

I had the mas unpluged and the car idled like crap and when I pluged it back in it was good again.

 

[SBR Joe]

No it revs pretty fine and it just got a new timing belt a month ago and no it doesn't just stop but it hardly goes anymore.

Thats kind of what i meant, . I would double check the timing, especially since it was messed with in the past month. Does it struggle to get past 5k, if at all?


Joe
SBR

 

[DSM90AWD]

I see you don't have any mods to circumvent fuel cut? Is that a possibility? Could also be a bad case of knock due to an over lean condition >> pulled timing (e.g. if your fuel filter hardline became kinked when you were trying to remove it).

Have you checked your plugs? Any CELs?

FYI.. definitely pickup a datalogger at your earliest convenience as makes troubleshooting much easier and with a modded car, a mandatory option to ensure a good tune and engine longevity

 

[Jordanbutter]

Yeah my testiment to the world that spark plugs will make or break a car. I pulled them out and the tips were white and the arms were red. I put NGK BPR7ES' in and its back to normal. And yes a pocket logger is my next mod to buy!