rb skipping, watch video

[Minuszero]

Hello, the video doesnt fully show how bad it is skipping, not really horrible just not right, if that makes sence.... anyways, i dont know, if it is worst case a valve is messed up, but would it smooth out above 2500 rpm and up? or could it be timing?.....i dont know I am lost at this point because I though I traced it down to the coil packs.... oh yeah its not better or worse with the gm coils its the same, and when it his boost it chops up a little sometimes and sometimes not?.....thank you to skipping rbs

http://www.youtube.com/watch?v=RkjcewP62SQ

[Carl H]

sounds like a bad ignitor.

[Minuszero]

thanks carl, is there any way to check it?.... by ohms or anything?...i dunno just a shot in the dark question...appericate it

[Carl H]

only real way is to test with a known good one, the fsm test isnt very accurate.

[Minuszero]

alright i will try to find one, thx

[KA720]

I've got one, and I may be heading to summit racing tomorrow, shoot me an e-mail [email protected]

[Minuszero]

sweet

[ninety1two40]

I have the same problem and tried a spare igniter I had laying around and it did the same thing, but that might be bad too. I even did the GM coil pack conversion, new plugs, different MAF some other things but no luck. Post the fix when you find it, I'll do the same.

[Carl H]

it may just be a dead ignition driver on the ecu.

[ninety1two40]

it may just be a dead ignition driver on the ecu.

Mine is skipping worse than the OP's. When I had the GM coil conversion I tested every spark plug wire with the timing light and they all seemed to skip randomly, except for cylinder 1, that wasn't skipping. I swapped with 3 different ignitor chips and another ECU (i'm running a PFC) and each ignitor chips kinda helped but still skipped. Checked my grounds, they seem good (~0.5ohm or less). Went back to the stock coil system since I converted to the GM coil pack to fix the skipping. What other things can effect the ignition system? PS, also checked the continuity of the ignition wires to the ECU.

[USMCgetsome]

ok 3 things to check.

Battery voltages/ alternator voltagesINJECTORS/FUEL SYSTEMTiming

Fellas if you've changed all your ignition system those would be the last things to check.

Btw. You always want to start basic.

Go back to a stock ecu stock injectors stock ignition. Otherwise you'll never know wtf just happened. unless you systematically uninstall each new upgrade to figure out what happened.

When i bought my first 240sx it came with an rb20 with a cracked turbine housing. It had an afc installed and man did it have the same issues. My alternator wasn't hooked up at all and it had 550 cc injectors installed. It had the same hiccups that you had in your video.

How i solved it. BOUGHT AN RB25DET and swapped it in. Good luck to ya.

[Acecool]

If it were the coilpacks you would have the issue at 4000-4500 rpm...

Since you did the gm conversion, make sure all the wires underneath are perfectly snug...

When I took my engine out and put it back in after replacing the throwout, it did the same thing - it was due to cyl 3/4 wire not being snug...

Could also be igniter... (which I also ended up replacing)

[rotorimp]

Do a compression check--that will also rule out allot of problems

[Minuszero]

Just a quick update.... out of all thing to go wrong, I was on my way to meet KA720 at summit yesterday, and about half way my TPS went out... Lost all power and would not rev past 2000 then would start acting like a rev limiter....the safc showed 0.0% when fully depressed, on side the road i tapped on the tps with a screwdriver and car would idle up and down .....so, I dont know if this could be part of it just the tps going bad or what,.... any ways after i got it back home i called the guy meeting me at summit and told him what was up, so i took my ignitor off and drove my truck up to meet him. We switched my ignitor out with his good one and with mine in his car it ran fine?....I am not that experienced with what problems a bad tps can do but could all of this be the tps symptions before it went bad?...... also since i have no parts (tps, ignitor) to go and put on I am going to do a compression check and will let you all know the out come.... thanks everyone for advice and help

[ninety1two40]

Any Update?

I have another IVAC to install and MAF on the way. Mine seems to be way worse and can barely rev past idle when it's cold in the morning. I have to hold the gas pedal down a bit to get it to rev up. After that it starts clearing up but still misses at 2000rpm and lower (I might not be able to tell if it's missing higher). Pulls pretty good though!

[Minuszero]

sorry for the late replys, anyway i will get them up tommorow. I have been busy and not had time. After the compression check i am going to swap out the cas. Buddy told me a 300z turbo car had the exact same problem and that is what it was. I have a friend who has a spare Cam Angle Sensor I will try tommorow if the compression check is positive

[USMCgetsome]

check those keyways on the input shaft on the cas! Sometimes they don't line up. Due to differences.

[Minuszero]

ok... video pretty much explains it all soo tell me what you think...thanks (if video doesnt work on your comp. i replaced the cas and it fixed it)

http://www.youtube.com/watch?v=UmIROxi0_js
Modified by Minuszero at 12:03 PM 9/5/2008

[Minuszero]

figured it out .... stupid grey wire broke for the safc under the dash that hooks up to tps... runs rich now though, may need to get tuned again. thanks for everyones help

[Yellow4g63]

Do you have a laptop?

[Minuszero]

Yes, why?

[USMCgetsome]

lol. After i saw the video i figured it out. lol. too bad u beat me to it. I tried changing my tps sensor with a z32 and did the same thing. Was going to say tps related. full throttle would just kill the motor.

[Yellow4g63]

Yes, why?

Look into a nistune daughter board to tune your car. Better control than the AFC.