Please HELP ME!!!

[awdfury]

I have a 93 240sx with an sr20det swap. The car has a front mount and a top mount tdo5 turbo upgrade. When driveing if you give the car more than half throttle it backfires and misses. If you keep it under half throttle you can drive the car all the way up to redline and it does fine. If you are not driveing you can stomp on the pedal and it will go to redline just fine. What do I do?? I don't know what to check anymore.

[SpeedMonkeyInc]

What spark plugs are you running and what are they gapped at?

[awdfury]

The plugs are bosch platinums. I can't remember what I set the gap at but it was the same as the plugs that came out of the motor when I got it. The plugs that came out where Ngks

[projectRDM]

The plugs are bosch platinums.

Bingo. Bosch plugs suck unless you drive a VW. Get some NGKs, gap them properly.

[infinitexsound]

spark plugs for sure...

[nonissan]

boost leak???

[awdfury]

What would the proper gap be for the plugs?

[awdfury]

Where do you think the vacuum leak would be? I have checked and can't find one. Could it posible be my wastegate or fuel delivery?? I am runing an external wastegate and I have it hooked up to the same hose as the factory would be.

[awdfury]

Switched to the old ngk's. The car will now boost to 5 lbs but it still cuts out.

[Shawn_of_the_Dead]

have you checked the current gap or anything to make sure they are all still correct? I would do that if you can't swap to new plugs yet. Find the correct gap...even did the search for ya. (http://www.zilvia.net/f/search.php?searchid=780206)

[awdfury]

Checked my gap I am at .028

[nonissan]

boost leak???


boost leak???

[awdfury]

bump
any other ideas I can't find a boost leak

[nonissan]

bump
any other ideas I can't find a boost leak

did you build a boost leak tester? or what did you do to look for leaks?

[awdfury]

one of the techs at work said to just spray brake cleaner on all of the joints in the lines and if the rpms raise then you have a leak at that point. If that is not correct how would i build a boost leak tester

[nonissan]

one of the techs at work said to just spray brake cleaner on all of the joints in the lines and if the rpms raise then you have a leak at that point. If that is not correct how would i build a boost leak tester

boost leaks will not always be evident at idle. you need to spray compressed air into your pipes and listen for leaks. do a search on how to build a testor. it's just a cap with a nipple for the compressor.

[steve shadows]

I have a 93 240sx with an sr20det swap. The car has a front mount and a top mount tdo5 turbo upgrade. When driveing if you give the car more than half throttle it backfires and misses. If you keep it under half throttle you can drive the car all the way up to redline and it does fine. If you are not driveing you can stomp on the pedal and it will go to redline just fine. What do I do?? I don't know what to check anymore.



kill yourself:loco:


naw i would check maf sensor first, and connection, then all the boost sytems, i think everyone has said that already, if everything check out perfect?

kill yourself:bigok:

[nonissan]

kill yourself:loco:


naw i would check maf sensor first, and connection, then all the boost sytems, i think everyone has said that already, if everything check out perfect?

kill yourself:bigok:

why check mafs if he can rev to redline?

[the head]

possible that the Maf calibration is off registering more metered air than that going into the engine causing a rich run conition thus expalining the bucking and backfiring

are you using an atomsphered BOV? if so which one?

[awdfury]

yes I am us an atmospheric bov. It is the turbosmart supersonic. I know that it works just fine because I used it on my Evo before I switched to an hks

[the head]

If you recirc the BOV you may get rid of the issue there...you are blowing out metered air which is probably (at lease somewhat) causing your rich run condition.

[awdfury]

the only problem with that is I am not blowing any air out of the bov when I am accelerating so how would that cause the problem

[awdfury]

Alright I have built a boost leak tester and tested for leaks. There are none. The vent to atmosphere bov can not be the problem because under load I am not relieving and pressure. The maf is connected properly ( I am goign to purchase a new harness though just to be safe). I switched back to the old plugs they are gapped a t .028 PLEASE any other ideas or anyone inthe local area want to take a peak.

[reactor]

Would this happen to be Joe's friend? Did you have a black EVO parked next to a charcoal metallic S13 on Thursday?

[nonissan]

how healthy is your engine? have you done a compression/leak down test? if that's not it, then i'd imagine it's one of your sensors.

[DP_Michelle G]

Which ngk's are you using 7's or 6's?

[awdfury]

Would this happen to be Joe's friend? Did you have a black EVO parked next to a charcoal metallic S13 on Thursday?



yes that was me was that your s13

[awdfury]

I am not sure what plugs they are

[Phlip]

I am not sure what plugs they are
Pull one of them out, it will be the last digit, usually in green on NGKs, on the side of the plug.

[reactor]

Yeah that was my S13, I'm a mechanic also. I work out of my garage. Maybe I could take a quick look for ya. But anything beyond a quick look I charge. You should stop by Fred Meyer sometime. Were you the one that looked under the hood of my car at Nissan that one time before you did your swap?

[g6civcx]

The vent to atmosphere bov can not be the problem because under load I am not relieving and pressure.

Any compressor bypass valve (CBV) or blow off valve (BOV) can leak at any time, even if you are under load and not relieving pressure. This is especially true on units that have really soft spring tension. Don't rule it out until you've verified.

[awdfury]

reactor yea that was me I work at Karmart. The guy at fairlady motorsports said that it is probably a fuel issue. I am giving him my harness on wednesday so that he can make sure it was done right. I would be interested in have ing you look at it. Also what would you charge if it got in depth. call me my name is Shaune 360-661-6805 What is your name??

[awdfury]

Alright well I give up. I am going to put the turbo kit up for sale PM me if you are interested.