[Gmecm] Re: Gmecm Digest, Vol 23, Issue 28

[Rsetina]

Cowen wrote:

>Can you trigger the solenoid manually, to confirm it
>works?  That would help rule out the ECM (I know
>you've tested for resistance etc, but what the heck).
>
>Is it stuck open, or closed?  In either case, is there
>an engine condition that would cause this (such as say
>high coolant temp, loss of ignition signal, I don't
>know??).  Look for a circuit that's actually supposed
>to lock out the solenoid, and if it exists, find out 
>if/why it's been triggered.
>
>Any  chance the wastegate itself is mechanically
>stuck?  Excess carbon buildup, corrosion, broken
>return spring, gate is loose on shaft (causing binding
>in bore)?
>
>I didn't know they made a 3.1 with turbo.  Is that the
>DOHC 3.1?
>
>Duncan
>
>  
>
>>I have a problem with a 1990 grand prix ste. The
>>wastegate solenoid 
>>won't operate. Its grounded by terminal a 18. The
>>tests say it's a bad 
>>ecm but ive tried  6 different ecms and 2 proms. 
>>What could possibly 
>>cause this besides a bad Quad driver? Tested
>>solenoid for low resistance 
>>and current draw tested grounds and power feeds to
>>ecm. all is ok. When 
>>you jump the aldl terminals all the other solenoids
>>and relays operate.  
>>    
>>
>
>
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> 
>Yes I can ground the wire going to the solenoid and turn it on. This closes the vac/pressure going to the wastegate actuator. It will then get full boost. in fact will go into over boost over 10.5 psi. ecm cuts fuel to protect engine. thats the way it was set up to work. my way around this was cutting the acuator rod threading it to make it adjustable. it works fine and runs good. But I would still like to figure out why the ecm won't ground it. there are no other problems that i can find. as far as i know there are no interlocks for the solenoid. Or are there??? The 3.1 is the pushrod engine they only made it in 89 and 90. This will be the first one I couldn't fix. I know I'm missing something but What? Thanks Bob S.
>