Backfiring under boost

[jrd450r]

I recently got my rb25det 240sx up and running and Ive been driving it around, and have an issue and want a opinion. When driving normally it runs perfect but if I get on it, once it gets up to 10lbs of boost and the wastegate opens, it just backfires and doesnt go. Im just running it with an open down pipe just to test it all out. I have a walbro 255 pump and no FPR so im thinking this may be the issue as theirs too much fuel pressure and its running to rich. Any thoughts? I also have a slow oil leak out of the oil line that runs into the bottom of the turbo, is there an o ring or gasket in there that I should replace? or how should I go about sealing it up? Thanks for the Help!

[eh?]

Make sure your timing is correct, plugs are gapped right and the coils are not cracked. Also get that FPR. For the turbo oil outlet, slap some ultra copper RTV on there an call it a day. You can buy gaskets off ebay if you feel like.

[matafied]

yea def change you plugs to start with and check those coils. i changed my plugs last week to clear mine up. happens to me alot and my problems have always been arching or fouled plugs. thats why i went all chevy on my ignition no more problems

[skylinegrl13]

agree with eh?, get a FPR.are you running the stock injectors? as you suggested backfiring can be caused from running too rich, are you planning to have it tuned after you "test it out?" if you are just driving it around to break it in and work out details, maybe save boosting for the tuning session.

good luck.

[blurrbosi]

^^^OMG HI2U!!

I recently got my rb25det 240sx up and running and Ive been driving it around, and have an issue and want a opinion. When driving normally it runs perfect but if I get on it, once it gets up to 10lbs of boost and the wastegate opens, it just backfires and doesnt go. Im just running it with an open down pipe just to test it all out. I have a walbro 255 pump and no FPR so im thinking this may be the issue as theirs too much fuel pressure and its running to rich. Any thoughts? I also have a slow oil leak out of the oil line that runs into the bottom of the turbo, is there an o ring or gasket in there that I should replace? or how should I go about sealing it up? Thanks for the Help!

Are you running stock ECU?

Stock Turbo, internal?

Did you put the boost up to 10?

Boost Controlled?

Have you Checked the plugs..., Look @ all the coil packs. (Take them out) Slightly pull on the rubber boot.... "gently" if it comes off... thats the issue...

BTW: Shaine thx for the coil packs, works great!


Modified by blurrbosi at 10:37 AM 8/6/2007

[jrd450r]

All my coil packs are fine, before I put the motor in I tested them all individually by rotating the CAS, they all look good visually also. I install a set of ngk iridium plugs when i put the motor in also, I believe I gapped them all at 0.9mm. I just have my waste gate running to my intake manifold since I don't have a boost controller yet.

[matafied]

^^^ BTW: Shaine thx for the coil packs, works great!

glad they worked out for you

[blurrbosi]

All my coil packs are fine, before I put the motor in I tested them all individually by rotating the CAS, they all look good visually also. I install a set of ngk iridium plugs when i put the motor in also, I believe I gapped them all at 0.9mm. I just have my waste gate running to my intake manifold since I don't have a boost controller yet.

yah but R U STOCK?