more DOHC issues

p8ntman442 · Post by **p8ntman442** » Mon Jun 04, 2007 11:37 am

how do you know?

Mach10 · Post by **Mach10** » Mon Jun 04, 2007 12:31 pm

It was rhetorical. :la:

But if you must know, it was doing a fuel system conversion on a late 80s ford Pickup. Had to relocate the sparkbox to the fenderwell (plastic). The ground we ran was grossly insufficient, and the thing would barely start, run like ass, and stall if you so much as touched the throttle :noway

Never even figured it out until we'd redone the harness a couple times and then clued in that the spark-box chassis was supposed to be grounded to the frame... Not along the harness connecting it to the distributor.

slow'n'steady · Post by **slow'n'steady** » Mon Jun 04, 2007 1:33 pm

here we go again...

got that grounded good, but now i have no injector spray. I took the UIM off, unplugged all the clips on the coil packs (just to be sure) and looked into the LIM while my buddy turned it over, and there wasnt a drop of fuel coming out any of the 6 injectors. Checked the fuel pressure again and it is still at about 41-42 pounds.

Dont have too much time to work on it so any quick guesses would be sweet! Also wanna say thanks for STILL not giving up on me even though im sure i have become the red-headed step child of the forum...

Kohburn · Post by **Kohburn** » Mon Jun 04, 2007 2:16 pm

no injector spray from any of the injectors while having pressure = bad injector wiring or ecm issue

The Dark Side of Will · Mon Jun 04, 2007 3:53 pm

Or reference pulse issue.

If the reference pulse was AFU because of the ground issue, then it could have been generating incoherent spark. Now that the ground issue is fixed, it might be a crank sensor problem. Does the tach indicate while you crank it now?

Mach10 · Post by **Mach10** » Mon Jun 04, 2007 4:08 pm

slow'n'steady wrote:here we go again...

got that grounded good, but now i have no injector spray. I took the UIM off, unplugged all the clips on the coil packs (just to be sure) and looked into the LIM while my buddy turned it over, and there wasnt a drop of fuel coming out any of the 6 injectors. Checked the fuel pressure again and it is still at about 41-42 pounds.

Dont have too much time to work on it so any quick guesses would be sweet! Also wanna say thanks for STILL not giving up on me even though im sure i have become the red-headed step child of the forum...

See in bold for why you weren't getting fuel.

The Dark Side of Will · Mon Jun 04, 2007 4:57 pm

oh yeah... duh. The reference pulse comes from the coil pack. If you unplug that, there will be no injector pulses or ignition signal.

slow'n'steady · Post by **slow'n'steady** » Mon Jun 04, 2007 4:59 pm

yeah Mach... figured that out after a bit

This shit is REALLY starting to get to me. I am back to thinking it is timing, so if it doesn't sell, i am gonna pull the engine and take it to a shop here in town and have them time it for me. I mean, it has fuel, spark and compression. It backfires out the intake so...
Tried gettin ahold of Erik to see if maybe i could pay him to come do it sense he is somewhat close but havent been able to get ahold of him. Also tried a bunch of differnt ECMs/PROMS, none of which made a difference of course...

Mach10 · Post by **Mach10** » Mon Jun 04, 2007 5:13 pm

Whoa, whoa, whoa....

You never mentioned ANYTHING about backfiring out the intake.

:cussing:

Did anyone ever pull your ignition pack apart? Any possibility that someone labelled the towers incorrectly (or hooked them up wrong) and that the only two cylinders that are firing properly are the middle ones?

You mention you tested compression. What were the numbers like? Bad cam timing will make the compression uneven--but not necessarily mean not getting any.

slow'n'steady · Post by **slow'n'steady** » Mon Jun 04, 2007 5:31 pm

Mach10 wrote:Whoa, whoa, whoa....

You never mentioned ANYTHING about backfiring out the intake.

:cussing:

Did anyone ever pull your ignition pack apart? Any possibility that someone labelled the towers incorrectly (or hooked them up wrong) and that the only two cylinders that are firing properly are the middle ones?

You mention you tested compression. What were the numbers like? Bad cam timing will make the compression uneven--but not necessarily mean not getting any.

i had the coils all tested an deverything. The backfiring MAY BE from the carb cleaner that i sprayed in the intake (which is why i didnt say anything, didnt spray very much though) Dont remember the compression numbers, i posted them on .NL and where told they are good.

Just had a lovely 10 minute arguement with a guy a Stewarts Performance. Told them i had the engine out of the car and needed the cam timing done. I told him it is a 3.4L DOHC form a '93 Lumina Z34. He said it isnt possible to time the engine out of the car. It has to be in the car and running so that he can adjust the dist. to get the timing right. I told him it is DIS he proceeded to argu more. I called him a fucking moron and hung up the phone. Still waiting on a couple places to call me back. But so far doesnt look too promising...

dratts · Post by **dratts** » Mon Jun 04, 2007 6:43 pm

I fully expect to log on here one day and find out that your car is running. I'm following this thread just to see when it is.

slow'n'steady · Post by **slow'n'steady** » Mon Jun 04, 2007 7:05 pm

dratts wrote:I fully expect to log on here one day and find out that your car is running. I'm following this thread just to see when it is.

im Glad SOMEONE is optomistic! i REALLY hope you are right and i REALLY hope it is very soon!!

p8ntman442 · Post by **p8ntman442** » Mon Jun 04, 2007 9:12 pm

my w41 calais got parked years ago after a full engine, tranny, and interior rebuild. I could never get the injectors to fire. Today, I bet it would take me a week at most to get it running. But its hours away, and I have my son now, and no time for it. Dont be like me, get this thing running, or you will kick yourself day after day.

slow'n'steady · Post by **slow'n'steady** » Mon Jun 04, 2007 10:15 pm

Well, i called around town today and only found one place that will even attempt it. He has to call be back tomarow and let me know wether or not he found the "tools" needed to do the job. If he says he cant find 'em, i am gonna drop the cradle, do the timing one more time myself and see what happens. I have a quick question on that.

I'm gonna post this again PLEASE tell me if it is right or wrong.

1. all cam gears "lose" (no lock rings) and all four cams flats up with the hold down tools in place and with tension on the timing belt

2. get the #1 cyl to TDC and reinstall lock rings on that bank

3. remove "flats up" tool from that bank (1-3-5)

4. turn the crankshaft one half rotation so that #4 is TDC

5. Reinstall lock rings on that bank (2-4-6)

6. remove "flats up" tool

7. engine should be timed correctly?!?!

Aaron · Post by **Aaron** » Mon Jun 04, 2007 10:22 pm

slow'n'steady wrote: 4. turn the crankshaft one full rotation so that #4 is TDC

Negative. Once you turn the motor over a full rotation, Cyl #1 should again be at TDC, but the back bank of cams should be flat down (Because cams turn at 1/2 of the crank), whereas the front cams will be flats up. Then lock the fronts, and you're good to go.

slow'n'steady · Post by **slow'n'steady** » Mon Jun 04, 2007 10:25 pm

Aaron wrote:
slow'n'steady wrote: 4. turn the crankshaft one full rotation so that #4 is TDC
Negative. Once you turn the motor over a full rotation, Cyl #1 should again be at TDC, but the back bank of cams should be flat down (Because cams turn at 1/2 of the crank), whereas the front cams will be flats up. Then lock the fronts, and you're good to go.

hehe... yeah it would...
So step 4 changed, now it should be right?

Aaron · Post by **Aaron** » Mon Jun 04, 2007 10:28 pm

Yes sir.

slow'n'steady · Post by **slow'n'steady** » Mon Jun 04, 2007 10:32 pm

cool... I popped the price on ebay up a little bit so im pretty sure it wont sell, but atleast that way i "tried".

One of the places i called today and was talking to about the fiero mentioned he seen the car. He was joking around and said he could do it, but then i would restart the auction and he would end up paying more so he's not going to... I did get quite a few compliments form him on it too. Honestly it made my day!

Mach10 · Post by **Mach10** » Tue Jun 05, 2007 10:14 am

slow'n'steady wrote:
i had the coils all tested an deverything. The backfiring MAY BE from the carb cleaner that i sprayed in the intake (which is why i didnt say anything, didnt spray very much though) Dont remember the compression numbers, i posted them on .NL and where told they are good.

Just had a lovely 10 minute arguement with a guy a Stewarts Performance. Told them i had the engine out of the car and needed the cam timing done. I told him it is a 3.4L DOHC form a '93 Lumina Z34. He said it isnt possible to time the engine out of the car. It has to be in the car and running so that he can adjust the dist. to get the timing right. I told him it is DIS he proceeded to argu more. I called him a fucking moron and hung up the phone. Still waiting on a couple places to call me back. But so far doesnt look too promising...

"Testing the Coils" just means that the electronics are reporting fine. If you've gotten the coil towers switched around on the module, you'll be firing in the WRONG ORDER, even if it tests "OK," since those test benches don't actually test where the spark is coming out, just that the module itself is responding correctly.

Aaron · Post by **Aaron** » Tue Jun 05, 2007 11:08 am

Mach10 wrote: "Testing the Coils" just means that the electronics are reporting fine. If you've gotten the coil towers switched around on the module, you'll be firing in the WRONG ORDER

I was under the impression that it doesn't matter which coil tower is on which pins on the ICM, you can switch them however you want, so long as the plug wires are still in the right order. The location on the module determines what cylinders they are for, not the numbers marked on the actual tower (Those are just for reference).