Engine Doesnt Want To Rev

[E-Z]

ok so i thought it was auto but after taking it to a shop and then ingeniously putting it in P and still wouldnt rev past 4-4500 we came to the conclusion some thing motor related is wrong, now im going through a process of elimination so far i have done TPS. next will be AFM but im starting to think possibly fuel reg or pump, possibly even exhaust blockage, it has always been hard to start cold, as in it wil fire 1-2 cyl at a time till all 6 fire up over about 10 secs.

the car is a cima with vg30det and front mount with stock exhaust, think cat may be hollowed out

ps when it revs it has no power its not like it cuts out its like i am towing a elephant and then stops at 4ish some times more, when it goes over 4 to like 5-6 it back fires loud

Edited March 20, 2009 by E-Z

[R33Matt]

I had the same problem with my R32. Around 4-5k it would start popping and backfiring. It turned out to be my coil packs. I sealed my coil packs up and then the car was fine after that Or you could buy some new ones. If that ends up being your problem

[reNEGaDe88]

back fire is not enough air or spark = too much unburnt fuel. check spark plugs. Intercooler piping would also cause that. Like an air leak after the AFM. Check vaccum line to ecu. That was my problem last week

[E-Z]

yeah i thought it was cooler aswell, i have re done it all and seems to be fine, could be coils i suppose but it doesnt mis fire and it makes boost and holds it, it only pops if i hold it down to push past 4k

[E-Z]

oh another thing, if its in N and i hold it down it will make full boost and sit on 4 ish for a while, like a launch controll

[R33Matt]

Yeah my R32 would hold boost and wouldnt miss unless it got to the 4k mark. Then it would pop and backfire. Best to check ya coilpacks and change the spark plugs at the same time.

[E-Z]

god damn it. this motor is a bitch to change plugs and coils on. cooler off, plenum off, heaps of stuff, oh well thanks heaps guys. keep more coming if you have more ideas, ill check this out soon

[PM-R33]

Change your plugs and go from there.

[E-Z]

put in new .8mm gap plugs and good working coils to no avail. advanced the timing to max and it works better but only runs 5 psi max now. my mate who is a bit of a guru think i might have slipped some teeth on the timing belt on some of the cams. it now hunts on idle and has a idle miss, im thinking thats just the .8mm plugs. going to pull the timing covers off and see if it all lines bak up. any other ideas?

[bubba]

Pretty strange that it will make "full" boost in neutral.. my guess is like your guru mate, it may have slipped a few teeth and the resultant retardation is aiding it in building boost (like launch control..)

[E-Z]

well timing belt looks like it had a bolt fall in some how it was thrahed im suprised it hasnt broken, i had a spare belt and chucked that on,. but the old belt was still doing its job, all timing marks lined up, im thinking maybe it has something to do with vct? could that be retarding the timing or something? car is pretty old and most wires are brittle. im going to check fuel filter and put a guage on to check pressure, car just seems really od,

thanks ryan

[E-Z]

yeah so there was a bolt sitting in in the crank case cover wearing the belt, but that wasnt the problem, so i replaced the belt anyway cos it was dodgy, and i found a big as vac leak from line which had popped off, that fixed the idle problem, and i cleaned the aiflow meter witch some metho. but it strated working better before that, so i actually dont know what fixked it, i think it could have bee that other belt was really streched but yeah, auto is shifting really fast into third, like 123 at 30kmh but i have been told thats just a tps adjustment. but im not entially sure it is fixed i guess time will tell. also what i done was put a one way valve in the fuel reg vac line so it will only see vac no boost as my car blows alot of black smoke on boost (before any of the previous problems) this is a remedy i read in a HPI magazine saying its a common over fueling problem and that will help. can any one confirm or any one disagree?

thanks heaps everyone for your input

Ryan

[EFI Performance]

You know where we are Ryan.......

We are as you know the diagnostic specialist.

Whitey

[ClutchBurndout-:(]

ok i had a similar problem, i cant exactly remember how i fixed it but it was around the time i was installing my boost guage, now i think it was running lean, and it popped and carried on with no power output, you should check the mixture?

[E-Z]

yeah yeah whitey haha i have already spoken to sean, if i have any more dramas its getting a v500 and manual valve body but untill then i would like to enjoy the car for a while without pyromania thoughts, which reminds me i should get fire and theft on it..

[CLNGMH]

  E-Z said:

, which reminds me i should get fire and theft on it..

hahahaha you bloddy penis.

Whitey

[bubba]

  E-Z said:

also what i done was put a one way valve in the fuel reg vac line so it will only see vac no boost as my car blows alot of black smoke on boost (before any of the previous problems) this is a remedy i read in a HPI magazine saying its a common over fueling problem and that will help. can any one confirm or any one disagree?

thanks heaps everyone for your input

Ryan

That's fkn dodgy as.. I'd get it on a dyno ASAP as it's mostly likely running dangerously lean at high boost/rpm.

[E-Z]

would i not hear it ping? yeah i might rip it out, it does say to have it checked on a dyno. well car is 100% again. from my conclusion it was cam timing from stretched belt, mixed with bad spark from coils and plugs, also my funny shifting patterns were due to a faulty TPS put the original one back on and all good, thanks everyone

[bubba]

When my stock fuel pump was dying (many moons ago), my RB20 was running about 13.5-14:1.. no audible pinging, it just went really hard..

[E-Z]

ok yeah i riped it off anyway just incase