SR20DET Breaking up under heavy acceleration. Tried some things already...

[Dori Dori]

Have you tried a different CAS yet? Also, don't overlook your grounds...make sure they are ALL there and have clean connections.

[MeanGreenS13]

grounds are all fine the problem is temperature sensative. It runs fine when its 80s outside or so but when it gets below 70 or so, it has problems. have not yet tried CAS

[MeanGreenS13]

bump COME ON! someone has to have an idea!

[Dori Dori]

You haven't swapped your CAS yet and you're turbo sounds messed up. Do you even have a boost gauge? You might be overboosting and not even know it (hence the craaaazy sound). Your stock wastegate vaccum could be leaking or not even connected. Your CAS could be messed up. You never mentioned exactly what you did to rule out the coilpacks.

[Fenvy]

what is breaking up?

[MeanGreenS13]

you should go back and read the entire post loveless. i dont feel like explaining everything all over again. ive ruled out Coilpacks, Plugs, Boost leaks, Bad turbo (this is the 2nd turbo ive had on with this problem) ECU, MAF, timing and a few other things slippping my mind at the moment.
Modified by MeanGreenS13 at 4:26 AM 1/24/2006

[MeanGreenS13]

Dori Dori, yes i have a boost gauge, when its cold i boost between 7 and 9psi and when its warm i hold at 7psi. ive already gone through all my lines 2 or 3 times. Every turbo ive had on my car has been crazy loud because of the lack of resonators or any type of baffling system in my exhaust. I am running lean right now, i have yet to try O2 Sensor or CAS but im REALLY leaning towards Head Temp Sensor, since my problem is temperature sensative and that is a temp sensor. It could be malfunctioning causing me to lean out and that is why im breaking up. BTW, when its warm, the car is no better really, it just doesnt break up. Still feels weak like its running lean.

[ericherm1]

I'm having the same problem... when I ease into the boost it will boost fine but if I mash on the gas it pops and hesitates hard.

How did you test your coilpacks? What #'s are you supposed to see on the Multimeter if you used one? Also if you tested your injectors what #'s are you supposed to see?

Not trying to highjack ... just following along because we have the exact same problem.

[MeanGreenS13]

somehow i have managed to crack a plug... that i did not see, i pulled it the other day and it fell apart in my hand, i have since replaced them and it went away. i do believe i was arcing through the side of the plug. problem solved. all i did was change the coilpacks to new ones by the way.

[karmakaze]

somehow i have managed to crack a plug... that i did not see, i pulled it the other day and it fell apart in my hand, i have since replaced them and it went away. i do believe i was arcing through the side of the plug. problem solved. all i did was change the coilpacks to new ones by the way.

FYI, you still have a problem. now you need to figure out why your spark plug cracked. (detonation)

are you still running lean? what is your A/F ratio?

you said you swapped out your FPR, are you still on the stock one? what fuel pump do you have?

[MeanGreenS13]

afr is 11.50-12.50 at 14psi... 255lph HP pump, and stock FPR right now... i dont have a problem i know why the plug cracked now. its fixed

[rustest86]

i know this thread is long dead but what plugs did you put in that cleared your problem up? i have the exact to the t problem as you did.

[MeanGreenS13]

holy **** back from the dead!! i just put in the same plugs, but new ones... what is yours doing...

[Thoughtful_One]

holy **** back from the dead!! i just put in the same plugs, but new ones... what is yours doing...

Sorry to bump such an old thread but my car is doing the same thing. The coilpacks check out, the plugs are brand new, TPS is adjusted, timing is correct (pulled the VC and verified the marks on the CAS), CAS has been checked with a known good one.

Breaks up at almost exactly 5500 RPM. Can go to redline if lightly on the gas, but at WOT, the car just breaks up.

I am completely lost and the car doesn't pull as hard as it should. S14 SR is boosting at a verified 9-10 PSI. Also, turbo does not sound loud. It's quite quiet actually; I have turbo back exhaust with a testpipe and HKS Hi-Power Exhaust.

Any ideas or things to check??

[rustest86]

i have a thread going but it hasnt been much help, but mine was doing the exactly the same thing yours was doing in the very same way...... a outside temp drop. i started having bad sputter at 5k then it would clear up as soon as it came, but we had a couple warmer days and it was fine. today it got cold again, it was back to bucking real bad at 5k. i had tried everything short of an ecu and plugs.the only plugs i could find in town that are even anywhere close were some bkr6e v powers and it cleared it right up. so im gonna order the right ones tomarrow.

i didnt want to spend $40 on a set of plugs if it wasnt gonna fix it.

[Thoughtful_One]

i have a thread going but it hasnt been much help, but mine was doing the exactly the same thing yours was doing in the very same way...... a outside temp drop. i started having bad sputter at 5k then it would clear up as soon as it came, but we had a couple warmer days and it was fine. today it got cold again, it was back to bucking real bad at 5k. i had tried everything short of an ecu and plugs.the only plugs i could find in town that are even anywhere close were some bkr6e v powers and it cleared it right up. so im gonna order the right ones tomarrow.

i didnt want to spend $40 on a set of plugs if it wasnt gonna fix it.

Also, my harness is brand new from Nissan. The car was also tested with a new S14 WC ECU and still the problem existed.

The shop who did the swap couldn't find the problem, so I'm going to pick the car up and change the 87 octane I put in there to super with some octane booster. I'll purchase the CRC MAF cleaner and clean the MAF as well. I don't know why I'm having this problem. Almost everything has been checked. I want to know what A/F's I'm running too but I don't have a wideband. Hopefully I'm not running too lean. The pump voltage on my brand new Walbro has been checked and it was fine.

If anyone can offer help, please email me.

The swap was done only one week ago, and I didn't even get to drive it yet.

[rustest86]

check the spark plug gap, stock gap is .09mm which is about .033 inches on a gapper. if your running more than 10psi, i was told to run .08mm gap which is .03 inches

[MeanGreenS13]

clean your MAF's

[Thoughtful_One]

My problem turned out to be my injeectors.

Shop took a closer look at them and they are 550 CC injectors out of a Twin-Turbo RX-7. Ran them with no tuning, hence the bad acceleration.

[xpicer]

im having the same problem i have recently rebuilded my engine and everything was doing fine until today it was sligthy warmer then the other days the car was runing fine, i accelerated the car on the highway i was at wot when i took my feet off the gass and put my car in neutral when the car died and didnt want to start back up and now i get this issue after a 5 minute drive , my temperature gauge does not go higher then the midle even when over hearing please help.

[MeanGreenS13]

this thread is about as old as my grandmother these days, i am not able to help anyone because i no longer own or care for SRs, please lock this up and start a new thread. Your problem will end up having nothing to do with my problem, they are 2 totally isolated things.

[silvia1]

My car is having the same issue. I have changed my plugs, adjusted gap, checked timming, changed fpr, checked good know maf, no boost leaks running 7 psi. PLZ HELP

[MeanGreenS13]

ZOMBIE THREAD RETURNS!!! AHHHHHHHHH!!!! you got a loose ground? how about a dying coilpack? hows your ignitor? what about the cam sensor, is it going bad?

[MeanGreenS13]

i started this thread 1/8/06. I fixed my problem.

Then another guy has a similar problem on 1/7/07... (he fixed his i assume)

now another guy has the same problem on 1/5/08....

Is this thread a yearly affair? like seeing the relitives you hate? JK =) hope what i posted helped haha.

[va240dude]

I have the same issue, checked wiring, CAS, timing, spark plugs/gap, MAF, boost leaks, BUT haven't swapped coil packs yet...what about the ground on the back of the engine for the coilpack, could that cause it? I can't remember if I tightened it all the way, it seems like its a PITA to get to from the top, is it easier to access from the bottom?

[fast_s13]

the ground is easy to tighten with a wrench..usaly if it breakes up in higher rpm its spark plugs or boost leak....

oh and meangreen. at least ppl are using the search button rather than starting a new thread.. there is good info in this thread

[MeanGreenS13]

yeah true, it just seems like a once a year epidemic, everyones cars get sick all at once.

[Fonz]

lol yea cause mine is doing the same thing and im trying to solve it . pain in the ***.

[MeanGreenS13]

ZOMBIE THREAD RETURNS!!! AHHHHHHHHH!!!! you got a loose ground? how about a dying coilpack? hows your ignitor? what about the cam sensor, is it going bad?

i levt a few nice suggestions here. Stuff i tried but didnt fix mine, but it doesnt mean it wouldnt fix yours. Give it a shot, im sure theres that off chance that your problem lies within one of these suggestions.

[Souless]

Same problem here too. Though mines isn't RPM specific, basically when I hit boost is when the problem starts. Here's my thread to better describe it:zer...rched

Tomorrow I'm trying a new CTS, MAF, Re-check ECU Codes, New ECU.