Pain in the ass backfire on 88 NA
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Pain in the *** backfire on 88 NA
I apologise if this was asked already, but I'm loosing my mind over it. My '88 NA VERT has a pain in the *** backfire when shifting gears at any RPM over 3K, its mild unless you get over 5k... Then its just real annoying. I swapped the ACV off of 88 engine with 50,000 miles on it (Mine has 170,000) and that stopped the backfire for a few months, but it came back about 1/2 yr later. I have heard it might be the ERG valve... Any guesses would be appreciated.
Thx in advance!
Thx in advance!
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uhmm... wow.. this is the first time I've heard this question, normally it's the exact opposite ("how do I shoot flames?")
so, ahh, somebody who doesn't just regurgitate stuff they picked up earlier had better answer this one... lol...
so, ahh, somebody who doesn't just regurgitate stuff they picked up earlier had better answer this one... lol...
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Actually I have the STOCK, yeah STOCK exhaust on right now with all (3) cats on.... And it does backfire that noticably!! But there is no power loss and this has been a problem for well over 1 1/2 yr! If I should be really scared please let me know.
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#9
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I'd ditch the stock cats soon. They clog & begin shortining engine life after 85K - 100K miles.
Most rx-7s will ignite the ritch exhaust fumes when you high rev the car. I prefer this, but if you want a muted car with no exaust note you'll need to run at least 2 catalytic converters (pre & main) and good mufflers (ie sucks power).
Make sure both catalytic converters are rated for the rotary engine's heat output.
Most rx-7s will ignite the ritch exhaust fumes when you high rev the car. I prefer this, but if you want a muted car with no exaust note you'll need to run at least 2 catalytic converters (pre & main) and good mufflers (ie sucks power).
Make sure both catalytic converters are rated for the rotary engine's heat output.
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No, I didn't change the small circle like valve under the ACV. I hear that could be a possible reason for the backfire. I had a Bonez dual cat midpipe but i fail emmisions (due to Jerseys new restrictions) so I threw the stock cats on there just to get my sticker. But it backfired with the other cats also....... ugh
#12
EGR Valve could be suspect. Check to see If It's holding vacuum. I have a Brand New one for sell If you need one. PM me for details
Also a faulty TPS Is usually accomadated with buckling at higher rpms load usually with a heavy load.
Also a faulty TPS Is usually accomadated with buckling at higher rpms load usually with a heavy load.
Last edited by silverrotor; 10-08-02 at 07:04 PM.
#13
Engine, Not Motor
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Bad EGR won't cause backfires, but a bad ACV certainly will. Also, adjust TPS and make sure your airpump (and related hoses) are in good condition.
Sounds like you're running too rich, which could be the things above, as well as (commonly) dirty injectors.
Sounds like you're running too rich, which could be the things above, as well as (commonly) dirty injectors.
#14
A bad EGR Valve could be attributed to back fire and a bad Idle.
Without the EGR Valve, your exhaust Is being expelled In the purest form. i.e lack of O2. That coupled with a faulty ACV or misadjusted TPS could all be considered suspect on having back fire. Or In my case running a Header straight pipe and a hi-flow exhaust.
Without the EGR Valve, your exhaust Is being expelled In the purest form. i.e lack of O2. That coupled with a faulty ACV or misadjusted TPS could all be considered suspect on having back fire. Or In my case running a Header straight pipe and a hi-flow exhaust.
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Originally posted by silverrotor
A bad EGR Valve could be attributed to back fire and a bad Idle.
A bad EGR Valve could be attributed to back fire and a bad Idle.
S5 cars ditched the EGR valve altogether, and they don't backfire...
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The car gets total **** gas mileage (200 miles a tank) if that is another symtom of the problem. Is there a vaccum test I can do on the ACV to see if the smaller valve is no good.... Doing some pondering on the ACV swap, I'm not sure how good the gasket on the "newer" ACV unit is. What are the odds its dirty injectors, cause that goes past my technical limits to remove them and get them cleaned. I have been told it could be the ERG, but at the same time people swear that the EGR doesnt affect backfires.
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I have a ACV bypass plate, I was thinking of removing and disabling the ACV for test purposes. BUT BEFORE I DID THIS! I wanted to ask you guys (more experienced) if this could harm anything. Or if I'd be wasting my time, I'm not worried about emissions legality anymore
so if you have experience or thoughts on the subject lemme know!
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