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

[MeanGreenS13]

When i take off in 1st and 2nd gear hard, the car breaks up like the spark is getting blown out. I went and i checked and re gapped all the plugs back to 30 (they had been crushed a little) but that didnt fix it. I tried swapping FPR's but that didnt work either. Then i re set my timing and still does the same. SO i did some searching and i heard that the CAS could cause that but i didnt know if that could be it, another thing we thought about was coilpacks. Can someone enlighten me on other possibilities?

[MeanGreenS13]

bump help

[BaliLover]

What boost are you hitting when its breaking up?

I gap my plugs to .28 and never had a problem.

It could be your MAFS, it could be overboosting, or it could be a slightly loose pipe or coupler in the system. Go make sure all of your clamps are tight on your intercooler piping, make sure your inlet tube to the turbo doesn't have any holes in it after the MAFS, and make sure you pull on your pipes to make sure they are being held really good with the couplers.

[MeanGreenS13]

the T25 does scream pretty loud, but i just think thats cause my exhaust isnt muffled in any way with resonators or anything. i hate hearing that MAF situation as i JUST bought a new one to replace one that was already ****ed up... im gonna get ahold of a boost leak tester from a friend of mine tonight but i need to get my compressor working to use it. Anyone else have any other suggestions?

[bdrifta]

how much boost are you running?

[MeanGreenS13]

fixed it was coilpacks

[S13FASTBACKSR]

do you know how many of your coilpacks were bad? the reason i ask is because i am having a similar problem and my #2 cyl. is burning rich so i only replaced the 2nd coilpack which didnt fix the problem. so now im wondering if it is more than one bad coilpack

[MeanGreenS13]

no idea, i had boost leaks too though

[BaliLover]

Could be a leaky injector on #2, or one that sticking

[MeanGreenS13]

breaking up again... heres a list of things ive tried

CoilpacksBoost LeaksTimingPlug Gapping

Next on the list is hopefully MAF and ECU... anyone else have ideas?

[MeanGreenS13]

riddle me this... the car only breaks up when its below 70 outside... wtf?

[dsm007]

if its temperature dependant when its cold outside then that sounds just like fuel cut ...colder temperatures=more oxygen in the air=more the ECU is seeing getting pulled through the MAF and then it happens....almost all factory turbo ECU's have fuel cut programmed into them to protect the engine when it see's a certain percent of air getting pulled through the MAF,like the vacume line popping off of the wastegate actuator is one good reason why its there...............do a search on fuel cut to see where people have hit it and to see what they did to set it back some so they dont hit it again.

[BaliLover]

YOu still haven't answered the question as to how much boost you're running. It sounds like you are overboosting, which occurs more frequently when its cold. What boost controller are you running, what boost are you running? Try running the stock wastegate with no boost controller and see if the problem still exists.

[nismotuner82]

he's running between 7 and 9...

[MeanGreenS13]

i have an HKS gate but im not gonna put it on till i get the problem fixed. I think im hitting fuel cut. i do have the stock 7psi gate... and did i ever mention the turbo is screaming loud? it sounds like my T28 use to, but then again, i dont have a resonator or any kind of muffling in the exhaust at all..

[Dori Dori]

Let me guess, you're using copper plugs? If so, get rid of them. I can't tell you why, maybe it's the coilpacks, but SR's hate them. I and many others had the same problems until switching back to iridiums. I ran one step colder coppers too btw, still broke up.

[MeanGreenS13]

i use NGK Iridium Heat range 7's...

[Dori Dori]

The plot thickens...how old are the plugs?

[MeanGreenS13]

fairly new, i have been enlightened by an SR20 local. he had a similar problem this week and it turned out to be a dirty MAF, im heading to get some contact cleaner tomorrow and clean my MAF out. I will post if it fixes or not. Keep tuned!

[dsm007]

That could be a very good possibilty of a dirty MAF.....if its dirty then the air wouldnt hit the hot wire inside of the MAF and cool it down.......the ECU would add more voltage to keep the wire hot and at the same time make the car run richer.....that could cause fuel cut in colder temperatures too.

[dsm007]

he's running between 7 and 9...

By the way nice pic of ya on new years eve of ya there lol.....maybe I will add one to my sig of a pic I took too....not of you of course lol

[MeanGreenS13]

heres to hoping, Im gonna go see mark today at nissan and get some cleaner and clean that ***** out. HOPEFULLY it will work. I really want to move on to my next part of this car... Battery RELOCATION! lol

[MeanGreenS13]

mass air is NOT the problem. I ruled that out today, Swapped with a secondary MAF i had here that i know is good, and it didnt work at all. Gonna try replacing the plugs next

[MeanGreenS13]

ok so... i dropped the gap to .28 on each plug. Made no difference... anyone ?

[S13FASTBACKSR]

im having a similar problem..ive done everything you have done and i also havent had any luck..the only thing ive done though that you havent is replace my ignitor but yet again no luck there, but it cant hurt trying since there are a lot of other SR's in vero that you can swap in for a minute to see if thats the problem..im actually going to swap a new ecu in right now to see if that fixes it but i doubt thats the problem but when i get done i'll post back and let you know

[MeanGreenS13]

emailed you, let me know asap!

[S13FASTBACKSR]

just swapped in the ecu i bought and it fixed my problem but i wouldnt bet my money on it just yet because the ecu could do the same thing your coilpacks did and only have fixed my problem for a day so we'll see what happens...im gonna keep driving it to see if i notice the problem anymore...and oh ya by the way i was running a 63 ecu however that shouldnt matter because i know plenty of people who run 63 ecu's with no problem what so ever and my 63 never gave me any problems until now (that is if it was the problem..but if it was thats just because it finally went bad) but if you want to drive to psl i'll be glad to let you swap my ecu in and see if that helps you out so you dont have to take a chance and spend $200 like i did good luck man

[S13FASTBACKSR]

hey phil just wanted to let you know that ecu has seemed to fix my problem. ive drove it around quite a bit since i put it in and not one problem

[MeanGreenS13]

unfortunately it hasnt fixed my problem, I even tried an ecu that has no fuel cut or speed limiter and the car just trips all overitself if i get into the gas hard. Mark suggested try the head temp sensor which i will and then the only other thing I could think of was cam angle sensor.

[MeanGreenS13]

anyone?