SR20 Forum banner
1 - 14 of 14 Posts

·
Registered
Joined
·
15 Posts
Discussion Starter · #1 ·
Hey everybody, I have just completed my swap on my 91 Infiniti G20. I havent really drove it much (just down the block and back). But in that short jaunt, I do have a question.

Now I never really got above 3500rpm at all, and maybe 1/2 throttle at the very most.

I am NOT running exhaust at all. I simply have the Turbo J-pipe on, and thats it. I am getting my exhaust done tomorrow actually (full 3").

I am running the stock DE ECU, the DE Sensors (all of them). Currently the only gauge I have hooked up is my oil pressure. I am awaiting for my Greddy Emanage, Holley Inline fuel pump, and my gauges (EGT, A/F, Oil Press, Oil Temp, Water Temp, and Boost), which will be ALL installed on the car before it is pushed to any limit.

My small drive today was just to see if everything turned over nicely.... check any problems with the install, etc.



Heres my problem.

When accellerating, I believe I am building a bit of boost. The engine seems to die out around 3500.... this could be my imagination however, as it was a momentary thing, then i immediately let off.....

But what would cause this?? Im almost 99% dead set that it is just fuel. I am running a 91 Infiniti.... original fuel pump.... I did put in a new fuel filter though, but im thinking..... with the engine at 1/2 throttle, at 3500rpm, it was probably around 2psi of boost, which means the MAF would be maxed out, then in turn my injectors would probably be at 100% ECU level.... then im imagining, that the boost started to build, which then caused it to lean out to the point that there was hesitation.... I did not hear detonation.... As I stated, I was off it immediately.....

Has anybody had this problem before upgrading to their SAFC, JWT, and fuel pumps?? Or is this another problem.

Also I have noticed Idle to fluctuate between 1000-2000rpm about every 5 seconds.... Im imagining this could be related to my crappy O2 sensor placement (wired to the bottom of the j-pipe), lack of backpressure (zero exhaust).

Anyways.... Im a new Nissan owner, never worked on one in my life..... Did the entire swap in about 16 hours of work.... just wanted some information!!! Thanks for all your help!!!
 

·
They're just cones!
Joined
·
1,941 Posts
CraigG20DET said:
Anyways.... Im a new Nissan owner, never worked on one in my life..... Did the entire swap in about 16 hours of work.... just wanted some information!!! Thanks for all your help!!!
16 hours first time? Holy crap!

We had the same deal when we did a DET swap. Changing the plugs made it a bit better, but it mostly worked itself out in the first week of driving. Not sure why it did that.
 

·
Registered
Joined
·
3,442 Posts
just like carlie said, or u should check ur plugs, wires
 

·
Registered
Joined
·
593 Posts
de ecu works like **** without a air fuel controller, try it with a det ecu. mine did the same thing. at the same time go get yourself some factory bkr6e plugs gapped at .030 and new plug wires always work best.
 

·
Registered
Joined
·
15 Posts
Discussion Starter · #6 ·
awesome!!! thanks for the responces guys....

I knew I needed to get plugs. Im just running Bosch Platinum +4s which were only 2 months old in my old SR20DE. I wont be using those again (not boost plugs at all from what i read). So im going with some NGK BKR7Es gapped to 30. Im running the DET ignition complete though.

I will be running a Greddy Emanage very soon. It arrives on Sunday, along with all my gauges....
 

·
Registered
Joined
·
15 Posts
Discussion Starter · #7 ·
Oh yeah, and another thing. I still have the JDM ECU, as well as the JDM Harness.... both of which ill be selling.... what do you guys think these are worth? The harness is uncut from ECU to end of engine.
 

·
Registered
Joined
·
269 Posts
the fuel pump should be fine. i ran my stock g20 fuel on 10psi all day for a good time before i switched to the walbro. i didnt know you could run the g20 ecu with the det. also the g20 ecu thinks you have 259cc injectors so youre getting way too much fuel for sure.
 

·
I look good going slow
Joined
·
1,161 Posts
It aint the fuel pump. I think you got a boost leak. My 93.5 g20 has the original pump and I got 304km on the clock it runs good.

Do you have your intercooler plumbing done? What engine, turbo etc. you got?
My g20 is stock my maf is not maxed and regardless of the plugs I had in there it ran fine. When my safc was at zero correction it ran fine, just rich
 

·
Registered
Joined
·
15 Posts
Discussion Starter · #10 ·
hmmmm.....

I am running a U12 BB. Right now I am running the stock top mount intercooler with all original piping. I havent gotten too carried away with that yet, as I want to get it running, and save money for possible repairs, rather than sinking a ton into an intercooler and piping.

Well i wont really know whats going on until I get my A/F, and the rest of my gauges.... I could have a boost leak (again, no boost gauge!)..... and of course, as I said, I never really pushed it at all, maybe 1/3 throttle.... I want to get the Emanage and all my gauges in, and of course my exhaust, before i go too crazy.

Another question..... when I swapped my DE sensors over.... I swapped EVERYTHING..... I mean every single sensor that was on the DE, I put on the DET. There were probably about 3 or 4 that were on the DE that werent on the DET. There was a sensor that goes underneath the intake manifold, it goes from one output on the manifold, into another... with a sensor inbetween.... the DET didnt have this.... but I put it on..... as well..... there was this whole confusing matrix of vaccuum lines that originally attached to the EGR and everything that I swapped over (except for the EGR parts). I had 2 extra vaccuum lines on that which I have capped off. I may have to do some vaccuum line rerouting, im not sure.....

Also, right beside the distributor, bolted onto the head, there is a sensor that sits on a 45 degree angle..... what is it?? hahah

Thanks again!
 

·
Registered
Joined
·
15 Posts
Discussion Starter · #11 ·
And also, one more thing, I do have the JDM ECU as well.... and I have the JDM MAF (which surprisingly is the EXACT same part number as the USDM DE MAF).

Now I have heard that running the JDM ECU requires to run a JDM O2 sensor.... is this true?
 

·
stirring but plain-faced
Joined
·
993 Posts
Will the car rev past 3500 when in neutral. If not it really sounds like you have a problem with the MAF. The car really should build boost and drive pretty well on the DE ECU. You will get pretty bad gas mileage and be running very rich, but the car will run. I drove my car for a good 2 weeks on the DE ECU before i got my JWT. Try re setting the TPS sensor if you have not already dont that, and bring the gap down on the plugs a bit.
 

·
Registered
Joined
·
269 Posts
CraigG20DET said:
Now I have heard that running the JDM ECU requires to run a JDM O2 sensor.... is this true?
well i tried running jdm o2 with usdm ecu on my 96 g20 and i could barely keep it idiling. so i would guess it would be the same way around in your case. but i was still capable of getting into boost. i would wait till you get your emanage setup before you start getting worried. the problem sounds very ecu related.
 

·
Registered
Joined
·
15 Posts
Discussion Starter · #14 ·
I put in some NGK plugs.... gapped them to .030 then I properly located the O2 in the J-pipe (the USDM O2). And my idle problem was more related to a tigher than normal throttle cable, so i backed that off a bit. And now it runs amazing. STILL NO EXHAUST THOUGH!! Argh, it was supposed to get done today, but now it got delayed until monday! My Emanage is showing up Sunday, so I think im just going to jump right into that.

Again thanks for all the help!! I will continue to ask questions! :)
 
1 - 14 of 14 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top