CPS misalignment?

[Greykier]

I am finishing a build on an '89 turbo. I managed to get the car running, though not well: it would not idle, and would run quite lean under throttle. Upon trying to adjust ignition timing, I discovered the CPS range of motion would not allow anywhere near proper ignition timing. I checked the CPS driven gear alignment and found it was off. I restabbed the CPS, per the TSRM, and now she won't start at all. I get sputtering and a few deafening backfires. I have rechecked the alignment twice with the same results. I rechecked spark, fuel delivery, and vacuum system. I am suspicious of the CPS. Is it possible for the CPS to suffer an internal alignment failure? If so, what's the fix? I have tried the wire wiggle thing to no avail. Any help is greatly appreciated as I am about ready to put a bullet through the block and buy a bus pass...

 

[shaeff]

Check cam/crank timing. Make sure that when the crank is at 0*, that both cams have the notches pointing at 12 o'clock. Pull #1 spark plug and confirm that the piston is in fact at top dead center, and that the crank pulley is tight and has not slipped.

When the cams/crank are at 0* TDC, THEN install the CPS per the TSRM instructions, or the instructions found here:
http://www.supramania.com/forums/showthread.php?t=38775&highlight=install+CPS*

 

[Greykier]

I already rechecked timing belt alignment just before reinstalling the CPS (at cylinder 1 TDC.) I did not, however, check for MIL codes. I will post my findings in a moment.

 

[shaeff]

Did you jumper t(e)1 and e1 when setting IGN timing?

 

[Greykier]

Ok, here are the codes and my theory for their presence:

code 14: Ignition coils unplugged while testing compression.

code 51: TPS unplugged while checking ISC valve operation.

I rechecked the connectors just now, all contacts ok.

 

[Greykier]

yes, I jumped the E1 and Te1 terminals, got the flashing CEL.

 

[shaeff]

No, I mean when setting the ignition timing, you need to have those terminals jumpered.

 

[Greykier]

Yes, I'm sorry, I wasn't clear. when attempting to set the timing, I had those terminals jumped. I had a friend in the car trying to hold the idle manually, while I tried to set timing. It seemed if I had been able to turn the CPS another 90 degrees (+/-) beyond the flange limit, it would have been dead on.

 

[GrimJack]

It's unlikely in the extreme that the CPS has suffered something internal. It's pretty easy to check, though - pull it and inspect the gear. The gear is held in place by a pin, and unless that pin is obviously messed up, the alignment has to be good. The shaft is more than tough enough to do some *serious* damage before it would twist.

Can you post the procedure you used to check your timing belt alignment?

 

[Greykier]

Cylinder 1 TDC (compression stroke); pulled #1 spark plug, inserted length of rubber hose to feel compression, used video bore scope to inspect vertical movement of piston, verified with crank pulley mark at 0.

Timing mark alignment; removed upper timing belt cover, verified marks on camshaft sprockets aligned with notches on rear sprocket cover.

rotated crankshaft clockwise two complete revolutions, reverified all timing marks.

I will recheck the CPS alignment again to make sure I was looking at the right thing. (self doubt has set in with a vengeance)

 

[Greykier]

well...

good news and bad news.

good news is I won't be getting a bus pass.

bad news is I won't be getting a bus pass because I probably would try getting one at an airport bar.

After ripping my hair out trying everything but the obvious, she's a runnin' strong. I pulled the CPS and restabbed. She started right up. Evidently, I aligned the driven gear pin, instead of the drill hole, with the groove on the housing. :kickinthenuts:

Thank you very much for the help. I believe I just needed a third party observation to re-center my logic. Thanks again for the advice. Back to lurking...at least i don't have to shoot her.