SR not starting...

[Turboed240]

Well, I am outa ideas. I replaced plugs and the fuel filter. The engine just cranks and once in awhile, I got a pop outa the exhaust. It will act like its gonna start for a sec but just keeps crankin. The fuel pump does run when I turn the key on and Ive checked the cylinders and they are wet along w/the plugs so the last 2 things I can think of to check are the igniter and coil packs. Anyone got any other ideas? Is it possible to check the coilpacks to see if they are bad?

[Cyberkreig]

Has the car ever run or are you still in the swap phase? Act like it is going to start? Does it fire on just one cylnder? What ECU do you have?

[Turboed240]

The swap is done...the car was running fine for about 2 months...it started stuttering around 3500-4500rpm about 3 weeks ago...it gradually got worse until the point that it was a miss...it was missing all the time though. It has the factory ECU. I pulled the old plugs out and none of them looked bad but I changed them just to be safe...I changed the fuel filter and Im waiting for my new fuel pump to come. I dont think it is a fuel problem since the cylinders are wet.

[Redline240]

Do you have spark? Compression? Did you check to see if any of the vacum lines are loose?

[Queamore]

Sounds like the distributer to me check and see if it's tight and check and see if the timeing is correct.

[Turboed240]

Now that was my next comment/question. It does sound like the timing may be off...how exactly do you check/adjust the timing on the SR motor? (Still learning this thing.)

[yellow_jacket]

If the timing was off you would have noticed a lack of power first. You would also be able to see where the distributor had moved from its original location. Not to mention that the plugs are wet which means you are either getting way to much fuel or no spark. You'll have to check for spark. If there isn't any on all 4 cylinders it could be the ignitor. It could also be a failure of the camshaft position sensor.(it is inside the "distributor")

[nismokid]

i thought the sr20 didn't have a distributor. doesn't it have coil packs??

[240_Keyy]

I think he means the CAS on the front right side of the motor, it kinda looks like a distributor.

[Turboed240]

So pretty much, I guess I can just set it up to see if all the coilpacks will "arc" when I crank the engine. If none of them are arcing, it's probably a bad igniter. If they are arcing, its probably a bad CAS. Correct me if I'm wrong here. Thanks again for all the help here.

[yellow_jacket]

If the CAS or the ignitor is bad you will have no spark. If you have a spark then it could be a timing problem. If you have spark and it's not a timing problem then it will be a miserable situation.

[Turboed240]

Okay...now is there anyway to determine if I have no spark, if it's either the igniter or the CAS? I dont feel like replacing both if I dont have to.

[yellow_jacket]

yes, but I don't know the procedure off hand. Maybe one of the Q45 guys could help you out if you search that board.

[Cyberkreig]

these files should answer all your questions. You will have to cut and paste them into your browser window, as tripod is gay and doesnt allow links.

http://cyberkreig.tripod.com/project/ca ... /p...r.gif

[Turboed240]

Now, the fact that the car "pops" from the exhaust once in awhile when Im crankin it, could it be the valve guides? Almost makes me think that i have a timing problem.

[yellow_jacket]

Valve guides bad, No. The pop is from the fuel igniting after it leave the combustion chamber. Can happen for various reasons. Check spark out of all four coil packs and get back to us.

[Turboed240]

I will check the igniter and the coilpacks tonite and let you know what I find. Thanks ALOT for the help.

[Turboed240]

Okay...got some new info here. I checked all the coil packs. They all fire. Here is the wierd thing. They will fire when I plug them into the first 2 coil plugs (towards the front of the car) but I get no spark with the back 2 coil plugs. The spark I get from the front 2 coil plugs is not a very consistant spark and is not very strong. What do ya think now? I checked the igniter and the coil packs using the tests above. Eevrything checked out ok so I am at a confusion here. Any ideas?

[Cyberkreig]

if the ignitor came out working correctly, and the coil packs themselves work.. it is possibly broken wires.. I'd suggest linking up test wires.. I can get you an igniton diagram if you need

[Turboed240]

Yeah, if you could I would appreciate it. The only thing that doesnt make sense is if it is broken wires, why when the car was running, did the problem gradually get worse and not just all of a sudden get bad. The car ran fine for awhile. It started hesitating a little around 3500-4500rpm and just gradually got worse till it was missing bad over the course of about a week. Then it went back to being not as bad and then got bad again over the course of about 2 days. I am thinking it is a faulty CAS.

[yellow_jacket]

I don't think so. I think Nils had this same problem. You may want to pm him and ask what he found because I can't remember.

[Cyberkreig]

The broken wire thing is just my guess.. If it was pinched somewhere and vibrated over time..

the CAS1 image on the previous page shows the test..

[Turboed240]

http://www.nissaninfiniticlub....16627There is the Nils problem. I read through it and cant figure out how to check the harness. Nils screen name is locked too.

[yellow_jacket]

Nils didn't have your problem apparently. What you will have to do is start tracing the wires from the coil packs back to the ecu. The other thing you need to check is the ground. make sure the coil packs are getting a good 12 volts.

[Turboed240]

Okay...well I think Ive cancelled out the possibility of a broken wire. We checked most of the wiring and didnt see anything. We checked the voltage at the coil plugs and they were all gettin 12v. I took a better look at my CAS and the wheel inside it isnt straight...it wobbles when it spins so I'm really thinkin/hopin that that is my problem. We shall see tomorrow.

[Turboed240]

Well, the car is running again and it is running "almost" perfect. Still a little studder in it but I think that is due to a lilttle needed tuning. The problem was with the wiring. I let the car idle and was looking at some of the wiring for the s-afc. Everytime I would wiggle one of the wires, the car's idle would fluctuate and I even got it to stall twice. I disconnected all the wiring...soldered AND crimped them all. The car started up and it runs and idles good now. Not perfect, but good. I am gonna put a SOHC MAF on it and do some tuning and everthing should be good to go.