Rebuild - The Saga Continues!!!!UPDATE

[napatiger]

Finally,

Got the engine back in, fresh rebuild.
----->UPDATED!!!
Turns out that the fucking first machine shop installed the #2 cam bearing with the oil hole thingy in the wrong position.
That is the main route of oil to the cams!!!!!!!!
No Fucking wonder I didn't have oil on the top end and my cam carrier took a big shit on the engine.
Damn I am so pissed, retarded bastards.

OK, I am done ranting.

The guy I am with now is the coolest machine shop guy ever, lets me hang out, ect. He knows an engineer for xxxxxx and has access to the CAD drawings for this engine!!! Don't even ask.

But maybe I can get an angle picture of the engine oiling system.

Anyways, the rebuild is continuing with .20 over pistons.

Sould be done soon. (I've heard that before)

-------->End Edit

Oil is fine, no leaks ect.

First, crank turns but no spark.

Fixed plug from Crank sensor to Coil packs

Next, turns over and backfires a little near intake.

Next, turns and sparks but no go.

Hmmmmmmmm.

I will borrow a Snap On scanner today.

Questions:

1) what do you think it is?

2) anybody use a scanner on 95 MC Z34, connections (IBDII?) and Cartrige (OBDI?) hints, help

thanks

mike

[napatiger]

Got the scanner, says their is no codes stored.....

Hmmmmmmmmmmmmm.

I ordered a connector for the CPS sensor and will replace tomorrow.
The scanner reads rpms, is that from the CPS?

What else should I check for spark?

[series8217]

First, confirm that your cam timing is correct. Flats up on one bank flats down on the other.
Make sure you put the cams in the proper banks. Reference the pictures in the timing article on this web site, you should be able to see pics of each bank with the flats up. Pay attention to where the lobes are on each cam.
Make sure you have gas in the tank.
Are the spark plugs fouled? Covered in gas?

[napatiger]

I already drained and filled with new gas..

I have good fuel pressure

Timing is good.

I really think it is spark, but that doesn't account for backfire.

I will check the plugs again, I know the plug wires are correct.

Maybe the timing, but I don't think so....

[napatiger]

checked compression 125 to 140 psi on all cylinders.

I think the CPS harness is shot, still does not work, will replace tomorrow.

gas, smudge on plugs.

[timg]

Is it sparking? Remove a plug and check for sure.

Tim

[SappySE107]

125-140 seems low but I guess the rings haven't sealed yet either. If the wiring to the CPS is not stock, you should replace it. Its picky as hell, i know that much.

[GTP091]

You should read my post on 'missing 3.4' if your having spark problems. I had similar symptoms to yours and it was the cps wiring. My car would not start it would only fire a little bit and then backfire out the intake when I had a delco ISm in it. My car would run very poorly on a non delco ICM (I still haven't figured that out yet). If you have delco parts in your ignition system rebuild your wiring harness for the CPS this may be your problem (make sure you use a drill to twist the wires - its very important).

[Jaysin]

I know this sounds dumb but when I built my engine I had the spark plug wires in backwards and it did almost the exact same thing. I had 1-3-5 switched with 2-4-6. I looked at timing and even thought I had intake and exhaust cams swapped. Took me 2 days for something sooooo dumb. Good luck!!

[napatiger]

I got the right plug (CPS) and will replace soon.

Thanks for the twisting tip. I have my spark wires correct.
I checked my compression by taking out all the sparkplugs first, does that give lower readings? But you are right, I haven't really seated the rings yet.

BTW The oil is circulating and seems that there wasn't much damage from the first startup, I think it got some oil the first time. I checked the main bearings when I installed the crank scraper.

Engine is looking nice, I will post pics soon.

[napatiger]

just had to switch the wires and she started right up. now for the next problem, see my other post.