Hi I have a 1993 rx7 that backfires everytime i decelerate or hit the gas, I noticed that when I add octane booster this helps a little but I still get a backfire. A friend said it could be dirty injectors or bad gas. Any help is greatly appreciated.

 

Id take it to the shop asap.

also..dont drive it like that.

let us know what the results are


j

 

If you have a downpipe or aftermarket exhaust, that causes backfiring and it's normal. Otherwise check the O2 sensor. Maybe you're running really rich.

 

what could be cauing is to run rich? thanks for your help.

 

Do you have any modifications on the car at all?

 

I have an aftermarket exhaust and down pipe.

 

That's what's causing the backfires. It's normal.

 

thats strange, it only recently started to backfire, ive had the mods for about six months.

 

although backfiring is perhaps common, it is not normal or "ok".

the car is running too rich.

clean your air filter, change your plugs (run NGKBUR7EQPs for the leading and 9EQPs for the trailing)

see how that helps you out.

 

I don't believe that in his case his car is running too rich. As soon as I replaced my pre-cat with downpipe and my cat back, I began to have the backfires.

Even though I shouldn't have ran the car this way without an upgraded ECU, for a while I ran with a complete exhaust (dp, hi-flo, cat-back) and intake. That should have leaned my car out quite a bit, but still had the backfires.

 

if you open up your exhaust your car will backfire and if its not your probably running lean however if its backfiring when you accelerated you may have a problem with injectors-plugs-fuel anything that would cause ignition or fuel to go on again of again.

 

Is there any place you recommend where I can get an upgraded ECU? What do they run? difficult to install?

 

Oh I forgot to add, i also have a hi-flow intake. Will these three mods cause the car to run lean. what would be the best way to fix that without an ECU upgrade?

 

do some research on it, search this site and visit these sites:
http://www.scuderiaciriani.com/rx7/index.html
http://www.rx7turboturbo.com/robrobinette/

Basically, you have 3 choices:
1. get your ecu reprogrammed (easiest) pettit, m2, etc....
buy one used off ebay or thepartstrader.com and sell your stock one, or just send yours off - $500 for new.

2. get a piggyback like the pfs pmc. this one you have to make the adjustments. get one used for around $500-700

3. go for a full ecu replacement like the very popular Apexi power fc. cost new is around $1100-1300 including the controller or every now and then one is found used for around $1000
(or you can wait and see how the new AEM unit does)

of course there aer other units out there, but you get the idea.

it all depends on how far you think you will go with the mods. go with 2 or 3, and you can eliminate the backfiring for sure. go with #1, i can't comment, because i don't have any experience with it.

good luck