seriuos sr problem need expert help

[nismonut21]

i have searched this problem on here over and over again and no one ever really posted what fixed there problem.when i start my car it idles perfect timing is set too 15 degrees. i drive down the road and punch it and it feels like i am at a rodeo riding a bull car starts breaking up really bad. i have all ready checked for boost leaks none present. i have checked the ecu and the little light goes out like it was designed to. i have checked throttle position sensor voltage it is correct. could a bad o2 sensor cause this to happen? same with the mass air flow? any help would be greatly appriciated thank you

[SR20Essex]

I'm in the exact same boat bro.

Ive searched and found everything from; boost leaks, to sensors gone bad, wiring harness problems, coil pack problems, and broken rocker arm.

mine started this crap last night; I was running it pretty hard, everything was fine, then all of the sudden it starts bucking and poping at 4500rpm's or full boost (~12psi).

Ive tried coil packs (no change), and checked wiring so far, when I get home later I will try looking for a boost leak or MAF problem (dirt, cracks, leaking hoses...etc.)

[SR20Essex]

Oh yea, I forgot fuel pump (or pressure regulator). That was mentioned too.

I plan on replacing my fuel filter, I'm running a 300zx filter that I put in about 10months ago. I don't think thats it, but its a cheap check.

[ILikeMy240sx]

Just out of curiosity... how are you guys checking for boost/vac leaks? The only way that Ive found to be effective is with a shop air compressor. Not your typical foot pump or electric pump.

Also, the LED on the ECU that is used for diagnostic purposes is supposed to blink not go completely off.

For example code 55 will give you five long blinks followed by 5 short blinks.

[driftin_sr20det]

Actually the light does go off. If you are not running a diagnostic the light comes on when you have the key in the on position, when you start the car it should shut off after a few seconds. If it doesn't, there is something wrong with the ECU. Just replaced mine because of it.

[otterman]

When you turn the key to on the light should turn on. When you start the key the light should turn off.

To run diagnostics:Set the key to onTurn the tiny screw beside the light clockwise all the way and the light should turn off.Wait 3 seconds and turn it back.Count the blinks.Turn the screw counterclockwise again for another 3 seconds to reset it.

11 Crank Angle Sensor/Camshaft Position Sensor.12 Air Flow Meter/Mass Air Flow Sensor.13 Engine Coolant Temperature Sensor.14 Vehicle Speed Sensor.21 Ignition Signal.22 Fuel Pump.23 Idle Switch.24 Throttle Valve Switch.25 Idle Speed Control Valve.28 Cooling Fan Circuit.31 ECM.32 EGR Function.33 Heated Oxygen Sensor.34 Knock Sensor.35 Exhaust Gas Temperature Sensor.36 EGR Control-Back Pressure Transducer.37 Knock Sensor.38 Right hand bank Closed Loop (B2).41 Intake Air Temperature Sensor.42 Fuel Temperature Sensor.43 Throttle Position Sensor.45 Injector Leak.47 Crankshaft Position Sensor.51 Injector Circuit.53 Oxygen Sensor.54 A/T Control.55 No Malfunction.63 No. 6 Cylinder Misfire.64 No. 5 Cylinder Misfire.65 No. 4 Cylinder Misfire.66 No. 3 Cylinder Misfire.67 No. 2 Cylinder Misfire.68 No. 1 Cylinder Misfire.71 Random Misfire.72 TWC Function right hand bank.73 TWC Function right hand bank.76 Fuel Injection System Function right hand bank.77 Rear Heated Oxygen Sensor Circuit.82 Crankshaft Position Sensor.84 A/T Diagnosis Communication Line.85 VTC Solenoid Valve Circuit.86 Fuel Injection System Function right hand bank.87 Canister Control Solenoid Valve Circuit.91 Front Heated Oxygen Sensor Heater Circuit right hand bank.94 TCC Solenoid Valve.95 Crankshaft Position Sensor.98 Engine Coolant Temperature Sensor.101 Front Heated Oxygen Sensor Heater Circuit right hand bank.103 Park/Neutral Position Switch Circuit.105 EGR and EGR Canister Control Solenoid Valve Circuit.108 Canister Purge Control Valve Circuit.

hope that helps.

[nismonut21]

aight i can work with this. i will try this now and let you know the results

[nismonut21]

with a boost leak tester and shop air

[da40]

i wouls still check that maf ..its a very common problem JUST DO IT!!! DO IT! DO IT!

[SR20Essex]

How do you check the MAF?... I have a votage meter / ohm meter

And I have a 25gal professional grade air compressor... How do I check for leaks with that?

I was afraid of using it for fear of creating too much pressure and blowing something.

[S13FASTBACKSR]

you check the maf using the volt meter...one of the wires for the maf should come up 12v the other 5v and the last is a ground

[SR20Essex]

Alright I think I found it. It was a case of spark plugs gone wild.

Notice the one on the right seems to be missing a bit of something.I think im running lean too, and these might be the wrong heat range.

I'm going out for a spin to see if it fixed it. I replaced those broken down NGK's (BKR6E) with some of my personal faves, Denso IK22's. For some reason despite what anyone else says, these rock!

Keep me updated on how you are progressing.

[S13FASTBACKSR]

ya the spark plug is definately F'd up