BLK13X

Hi guys, need some info desperately!

My car's been in the shop for the last two weeks or so now, getting the turbos changed (as one's blown) and there's a stupid misfire in the car. Trying to diagnose what the friggen problem is. Now, the spark plugs have been replaced (they only saw 7000kms of driving or so), the coils and ignitor have been tested (turned out A OK), connectors have been replaced to new ones... can't seem to find the problem? It seems whenever a coil is connected up to cylinder 5 there's a very minute spark (compared to the other cylinders, where it's firing perfectly). Engine's a 1JZGTE.

So where do I look now for clues? Could it be a dead ECU? Does it sound like an electrical ghost? Hoping it's not the wiring otherwise it's gonna be a pain in the proverbial ****...



Jose

prjctSC300

iTrader: (1)

could be a bad valve??

BLK13X

How can you tell? I've never had this problem before so I dunno what to do.

prjctSC300

iTrader: (1)

i suggest you do a leak down test and see if that cylinder has the same readings or similar than the other cylinders..let me know what the readings are

bean_8044

If theres a smaller spark than the other cylinders than it has to be the something on that line from the Ignitor to the spark plug. I would try swapping coils, with the same spark plug in there. Check the output of the spark plug on whatever cylinder you swapped the cyl 5 coil to and compare. If the coil does the same on the other cylinder, then you know its the coil. If it doesnt, and cyl 5 still has weak output then look into the spark plug or the wires going to the ignitor. The ignitor should have just a single channel burnt out on it, but it may.

BLK13X

Thanks a lot for the suggestions guys, will do!

So from what I can see from the replies, there could be something wrong in the wiring between the ignitor and the coilpack itself? The mechanic swapped coils from the other cylinders (which are firing perfectly), it only happens on cylinder 5?

prjctSC300, leak down test? Please explain. My car's never been in so much ish before hehe...

Thanks

Jose

bean_8044

My understanding of the stock ignition system is that the ECU will send out a signal to the Ignitor based on a Crank Angle Sensor. The ignitor sends out a base voltage, around 200-300v maybe which gets amplified at the Coils, which are independant of each other and fire two at a time. Im not ruling out some bad engine work, but it seems like its just in the ignition system. Have you checked the plugs recently for more fouling on #5?

BLK13X

The car's down at the shop

BLK13X

That's what we were doing at the shop, and any coil that was attatched up to cyl5 sparked really small compared to the normal spark on the other cylinders. So, if there's something wrong with the crank angle sensor it could screw up the signals sent then, correct? Also the plugs have jsut been changed (down at the workshop) with brand new Denso's.

Cheers

Jose

prjctSC300

iTrader: (1)

check the resistance of the wires for that coil?? maybe too high resistance could be the cause of low spark???

BLK13X

I was speaking to the mechanic today, he said that my ECU was throwing up some really whack voltages and signals... anyone ever had this problem before?

bean_8044

If your ecu got wet i can see it happening. Electronics are very strange sometimes. It shouldnt be the Crank Angle Sensor since it wouldnt affect just one cylinder. I dont know how the ECU fires the ignitor either, so it may be a plausable idea. Its pretty easy to pick up another ECU and throw it in there fast though

BLK13X

Update: Tried switching the following... (between my car and a donor (ie. a buddy's) Soarer 2.5GT)
* ECUs
* Ignitors
* Coilpacks
... to no avail. Now I'm relaly thinking it's the wiring somewhere that's f*<Ked up.

kevro

iTrader: (2)

any answers yet? My cart still has the stock 2jz-ge and Im having problems with the number 5 cyl. I have changed everthing and still have nothing going on in that cyl.

NoLongerA13bFan

iTrader: (2)

Did you ever figure out why your number 5 was not firing?