loosing power under full throttle

**wannabeS4** · 08-20-2008 08:31 PM

Ok so today I was on getting on the freeway and was in third gear. I go wot and around 4k rpm and it has trouble getting pass that point. So I try the same thing in 5th gear and it does the same thing. It feels like its loosing boost and bogging down its not throwing cel it feels like boost leak cause it kinda sputters like the boost is coming and going. What could be the problem.

**1997gtx** · 08-20-2008 08:34 PM

A boost leak normally doesn't keep the car from revving. It keeps the car from boosting.

Is it boosting fine until the bog? Do you have a boost gauge?

What you're experiencing sounds more like a misfire. Could be from a number of things ...

Only way to tell for sure is to scan it. I wouldn't be surprised to see a few 'hidden' CELs.
--Adam

**wannabeS4** · 08-20-2008 08:41 PM

Originally Posted by 1997gtx

A boost leak normally doesn't keep the car from revving. It keeps the car from boosting.

Is it boosting fine until the bog? Do you have a boost gauge?

What you're experiencing sounds more like a misfire. Could be from a number of things ...

Only way to tell for sure is to scan it. I wouldn't be surprised to see a few 'hidden' CELs.
--Adam

It feels like its boosting until until it boggs down. I don't have a boost guage I haven't picked one up yet I just picked up the car last week. I guess I need to get it scanned. What would cause a misfire. Cause it just started today out of nowhere.

**Jung** · 08-20-2008 09:16 PM

It could be a whole slew of things. When my maxima misfired, it did it reallllly badly, and i oculdnt get past 3 grand for a while sometimes. It would stutter and hesitate and not accelerate. Bad plugs, bad grounding, 02s, EGTS, etc...

I've also heard that clogged/bad fuel filters can really hold back the potential of the car, since it can't draw enough fuel, and it can cause really shitty mileage. what are you averaging now?

It doesnt sound like limp mode, since it would still accelerate, but would not be as strong

I had a bad MAF for a while, and when running at WOT in 3rd or any gear really, it would stutter sometimes.

definitely give it a scan

**NogaroWonda00** · 08-20-2008 10:20 PM

Pressure test it! spray soapy water on all the hoses and connections see if you see any bubbling.

Chances are that its probably your throttle-body boot or possibly an F-hose. if I was you I would take the t-body boot off completely and check for cracks. thats my first guess and I'd check that first before checking:
spark plugs- make sure the gap is correct. What plugs are you using?
then if that doesn't fix it i bet it might be the fuel filter.

your in 2nd gear low rpms you floor it and everything is cool till 4000 rpm then it backfires? is it building boost fine when you ease into it?

**wannabeS4** · 08-20-2008 10:55 PM

in every gear when i go wot everything is ok until I get to 4k and then it starts stuttering and cant really go higher in the rpm range. I guess im going to take it a shop to have it scanned. IM going to check the tbb and other hoses right now.

**1997gtx** · 08-21-2008 08:18 AM

It could be a boost leak if it's really bad ... and effects the fuel delivery, etc ... I would lean more towards a bad EGT or another component of the fueling system. But you really won't know till it's scanned and pressure tested. Could very well be a bad boost leak.
--Adam

**wannabeS4** · 08-21-2008 10:38 AM

well i just got back from the shop, had it scanned and it was misfiring in cylinder 3. Had a boost leak, my diverter valves were dead. So since the previous owner hadnt done the spark plugs so im going to do that and the coil packs at the same time.

**NogaroWonda00** · 08-25-2008 09:40 AM

tell whoever is working on it to open the butterfly when pressure testing see if the throttle-body boot is shot too itd be easier to put all of that in at the sametime (DV's/T-BB)