SR20DET problems.

[Hatchman]

Some things came up and I have not been able to go to the shop yet it'll be after thanksgiving before I can go, sorry

[WestTxSR20Tuner]

I tried my friends wiring harness and tuned ECU. No luck it does the same thing so its not the harness or ECU.

[Hatchman]

Yeah they swapped out my harness and ECU from a running 240 and it did the same thing also.What was your friends ECU tuned for?I'm pretty sure I'm going to the shop Thursday so I'll see whats going on up there

[WestTxSR20Tuner]

I am not 100% sure but his setup is almost the same as mine only I am runing a Z32 MAF. Its tuned for non recirculating BOV, no speed limitor, 7600 rpm, and the upgraded fuel pump (walbro 255lp). I tried new vacum line with not luck. I am going to try another CAS. Some posts said to try swaping some relays because they might be going out. SOme other people suggested getting a new chassis harness because it might be shorting out the fuel pump. I pulled off my fuel rail and I could see the injectors squirting fuel. Another suggestion was another FPR to keep up with the fuel the pump. I think its some sensor that is jacking the firing of the spark to the motor. like a knock sensor or some thing.

[WestTxSR20Tuner]

Before I could swap the CAS I went to give it a test start and it won't fire up. It turns over but never starts. what causes no spark besides plugs and wiring? when I change the CAS I will try to use my spark plug tester and see if its stil sparking.

[skaterfromvt]

no spark in any cylinders could be because bad cas or wireing to cas...also if its not cracking over...pull your ecu apart and check to see if it looks like this....

zerothread?id=265103

if your ecu is fried...that would more then likely be because of your maf being wired wrong or the wires grounding out on themselfs...you can send your ecu to best1tuning.com and they have been able to repair the ecu's....

im thinking its fried ecu...

if not then the cas is installed wrong make sure you install it with the dots lined up...and check your knock sensor...

when i first got my blacktop....i had a bad knock sensor and only 3 plugs were sparking...pulled the cas out and put it back in and then none would fire...then once i got them to fire again my maf wires touched and grounded out and friend my ecu...the enging will turn over but it would crank..

and one more thing...check your fuse box there is a ign fuse that could also cause some of your problems...

let me know good luck
Modified by skaterfromvt at 3:56 PM 12/3/2008

[duffman1278]

^^^ WTF if up with that link? Why are you posting random "spyware removal" s***???

[skaterfromvt]

nah man i posted it as the forums page it must have changed to that!..i just clicked paste again and it was the same link it was still copied...f'n weird!

[WestTxSR20Tuner]

I tried a new CAS and it did not change any thing.

[Hatchman]

I still havent been able yo go to the shop but I did call and they said they were making progress but its still not running a 100%,the guy said it was the most difficult car hes ever worked on and hes about 103 so I feel kinda proud and dissapointed at the same time.Maybe next week I can go .Well on the bright side I got alot of stuff to check and maybe one of them fixes it.If anybody else has had similar problems post em up the worst thing that could happen is you help somebody(sorry to sound gay).

[skaterfromvt]

I tried a new CAS and it did not change any thing.

did you install the cas right? did you check timing with a gun?

[WestTxSR20Tuner]

I know a guy that is certified Nissan mechanic. he's going to barrow thier scan tool and come help me track down the issue for a fair fee.

[nuts510]

Have you checked for codes, if it's giving the air mass sender code check for broken wires between the ECU plug and the airflow meter plug with a meter also make sure the 2 wires that are inside the shielded housing are not shorted to ground I have ran into that problem twice it is a ***** to find

[WestTxSR20Tuner]

I am pretty sure the CAS is installed correctly. I did it on my friend's SR20 and it worked. Can you descibe where this shield housing in more detail? I want to be sure I am checking the proper place because it would make sense.

[WestTxSR20Tuner]

Oh ya my ECU reads 55.

[Hatchman]

Yeah mine throws a 55 also or at least it did last time I was near my car.Is the MAFS a code 12 because it thew that once before and I was under the impression that the coolent temp. sensor was a code 12.They changed out the coolent temp. sensor by the way.

[WestTxSR20Tuner]

Did it change any thing?

[Hatchman]

Yeah when they changed the coolent temp. sensor and the throttle body it actually started and stays running with the MAFS unplugged.

[WestTxSR20Tuner]

Did it change any thing?

[WestTxSR20Tuner]

The coolant and knock sensor are the only 2 I have not changed. As soon as it warms up I will have to try that. The mechanic that is supose to come look at my car keeps flaking out on me. So, I am tempted to buy the OBD scan tool and learn how to use it my self.

[WestTxSR20Tuner]

I changed the coolant sensor and the whatever that little senor is next to it and did not change any thing. Still no spark.

[skaterfromvt]

fyi both are coolant temp sensors...the one on the left is for the ecu and the one on the right is for your dash so if your dash coolant temp isnt working then that could be why...

No spark - replace your knock sensor its never bad to have a new knock sensor....

No spark - make sure your COIL PACK HARNESS IS GROUNDED... with that wire on the back of the motor!!!!

OR EVEN MORE OBVIOUS - IGNITION CHIP? CHECK VOLTS BEFORE AND AFTER CHIP!!!

cranking and running with the MAF unpluged...bad MAF??? bad maf wiring...(if it runs fine with the maf unplugged up to 2500 rpms its because the computer defaults the air-fuel mixture and makes it rich....this could also be an pre turbo exhaust leak...

[duffman1278]

Unwrap your wire loom going to and from your coil packs and VERIFY that the wires are not touching each other or a gound is missing.

Before that, test each of your coilpacks with a multimeter like the FSM says.

[WestTxSR20Tuner]

I swapped a harness off a working SR20 swap includding the ignitor chip and I have 3 ECUs. That ground on the back of the coil pack harness is bolted to the firewall. Dumb question but where is the knock sensor? I might have already swapped it out. It went from starting to not sparking. And when it would it die after3 - 4 minutes w/ or w/ out the MAF plugged in. At first with idle for days with MAF unplaged. I will try checking the wires on the coil pack harness?

[WestTxSR20Tuner]

Is there any wiring inside the car that would cause this? I had a problem a while back where the car would not crank because some wires in the fuse panel were pulled out so I stuck them back in the fuse panel under the dash on the driver side.

[skaterfromvt]

if you want try this...2 things

take out the spark plug from the first cylinder drop a large screw driver down inside so you can see when the piston is tdc and turn the engine over by hand i think its a 27mm....and make sure when the screw driver is all the way at its highest point that the timing marks are lined up!...if so then your timing is probally close to what it needs to be

NEXT HAVE LOOSEN THE CAS BOLTS AND HAVE A BUDDY CRANK YOUR CAR WHILE YOU TURN THE CAS PLUS OR MINUS THE 15 DEGREE'S....HAVE THEM CRANK THE CAR IN 15 TO 20 SECOND INTERVALS WHILE YOU SLOWLY TURN THE CAS...TO SEE IF U CAN GET IT TO CRANK THAT WAY...

OR IF YOUR NOT SURE IF YOUR GETTING SPARK YOU CAN TAKE A COIL PLUG AND PLUG OUT OF ITS CYLINDER AND SET IT ON YOUR EXHAUST MANIFOLD AND DO THE SAME THING AS ABOVE..CRANK IT WITH THE PLUG TOUCHING THE MANI AND TURN THE CAS...

[WestTxSR20Tuner]

I changed the coolant sensor and the whatever that little senor is next to it and did not change any thing. Still no spark.

[WestTxSR20Tuner]

I changed the coolant sensor and the whatever that little senor is next to it and did not change any thing. Still no spark.

[mdgeist]

i have a similar problem, but my car cranks up and runs.my car wont rev past 2500. i have a new "coolant temperature sensor and "s13 sr20det MAF".i also searched the net and asked other tuners. they all said that its MAF related.could it be the wiring? cause the wiring was done by yury from wiringspecialties.com.i bought the swap from the previous owner which he only drove for 2 oil changes, and the swap was running before he stored it.

[Hatchman]

Is your MAFS plugged in?I also had my wiring done by wiring specialties and from what ive heard wiring specialties kicks *** so im still reluctant to believe it is the wiring.How long was your car stored?