f9802159

i have an 87 tll 96000 miles on it....after 3,000 rpms all you hear is loud popping...i replaced the acv and it didnt make a difference....the weird thing(at least it seems weird) is that my stock boost guage maxes out and it actually passes the line....thats when all the popping begins...i dont think its fuel cut because all i have done to it is a cat-bacl exuast....please help me out!!!!!!!

Madrx7racer

welcome to the RX7 world....once you get straight pipes those pops will turn into flames. You're prolly running rich.........seach for Afterburn, backfire etc.

f9802159

damn!... can i still pass emissions?i havent tried...didnt think

Madrx7racer

is it a bone stock TII? Have you done a tune up?

Mint87RX7

your guage is showing you boost spikes, check your turbo system before you blow your engine

Madrx7racer

that guage is unreliable anyways so I doubt it is working properly.......

MARTIN

check out your wastegate line, make sure its connected, looks like it might of come loose....if not, then you might have a boost leak.....cus it sounds like boost cut to me

therotaryrocket

yea, sounds like a seized or disconnected wastegate, then your hitting boost fuel cut. you don't happen to have an exhaust leak do you?

Icemark

don't forget to check the TPS as well. Common to have backfires if it is out of adjustment or failed.

f9802159

i havent checked the wastegate its sounds like it could be it....and i have a cat back exhuast....when i changed it the mechanic said that my main cat is bad.....im trying to get that racing beat dp and presilencer......ill checl on the wastegate tomorrow and ill let yall know.....could it also be the 02 sensor?

SupraBen

What PSI do is fuel cut usually set at? I have an FCD, so I've never actually hit fuel cut.

MARTIN

I've never seen a faulty tps give a symptom lke that, if a tps is bad you would know cause of the idle, and also popping during deceleration and compresion braking...

therotaryrocket

fuel cut is supposed to hit 1 psi over stock boost setting. I think you should check your tps, isn't it easier than checking the wastegate?

Sideways7

iTrader: (7)

Off the top of my head, the stock fuel cut is at 8.6 PSI.

vicious525E

i have my money on the waste gate, he doesnt seem to be having idle issues, a common sign of tps issues.


but just incase it is your tps and you dont already know:

to test:
http://rx7turbo.com/tpstest.htm

and to adjust:
http://rx7turbo.com/tpsadjustment.htm

MARTIN

the wastegate is easier than checking the tps.... one, make sure the line from the turbo to the actuator is on, second grap the rod push it away from the front of the car. make sure its not excessively hard to move..plus if you dont have a rough idle then you most likely dont have a tps problem..

88t2romad

just floor it harder!

88t2romad

kidding^^^

f9802159

well right now i have an idle problem but thats because my throttle cable is tooo tight....i removed my throttle body and didnt check that cable...i dont think i have a bad tps....i talked to someone about porting my wastegate today(cause i dont want to mess anything up) but i had no i dea i had to take the turbo off...so now im gonna take it to a performance shop and see if they can do that for me.....i thnk it really is the wastegate though....it makes sense.... so when you hit boost cut you start backfiring?how is that

josh greene

Did you ever find out what it was I was just driving my car 87 TII and at fuel cut it started back fireing????

f9802159

No....not yet...im still working on it....i replaced the wastegate actuator line and its fine....it moves freely....the tps isnt the problem....I emailed a guy at rotary ressurection and he said it most likely the secondary injectors.One of them may not be coming on..He said check a "resistor pack" under the afm but i have no idea what that looks like...so im just having someone else take a look at it....it may also be the wiring..Did your car sounds like poppin popcorn?

Madrx7racer

mine does that all the time.....loud as **** too

josh greene

My car had a nice tone to the exhaust, now a week later it sounds like a duck when i get on it...It only back fired once scared the **** out of me thought i broke something!!! but seems to be working ok hasnt back fired again "YET"...

cezonetheillest

mine makes a really loud back fire and also 2 foot flames out the mufflers. i like it.