Re: acelleration problem?
 

hi all, Harold again, we pulled the plenum off to check for vacuum leaks and found none, dont have a tech 1 tool ,so im kind of lost. is there a way to check the vacuum solenoid or am i looking in the wrong place?to refresh your memory, i have a code 61, and have replaced both fuel pumps and socks and both o2 sensors ,checked all vacuum lines outside and under the plenum. nothing has helped. HELP!!! HAROLD

Re: acelleration problem?
 

You can stumble through without a tech 1, but you will need a scan tool... and I'm not talking about just a code reader. You need to see sensor outputs.

The results of the dig tree are either faulty connection/faulty ecm/faulty solenoid/faulty actuator or hose.

Re: acelleration problem?
 

just an Idea did you ck each of the actuators to see if they are opening the secondary throttle blades and individually holding vaccume?

Re: acelleration problem?
 

Harold,

I just went thru this DTC 61 on my 90. I didn't have the correct software for my scan tool which meant that I could not do the "Feild Tests" required by the diagnostic flow chart in the FSM.

It comes down to the situation that you are reasonable sure that the vacuum connections and all the vacuum equipment works, holds vacuum? If yes then the fault or source of the 61 is electrical. Therefore the only three possible electrical items are:

2* control solenoid, can hold vacuum but not open on command from ECM. Coil part is fried or something?

ECM, I think all it does is ground the solenoid??? so it opens.

MAP sensor t-ed off of the left actuator. That MAP is under the ECM brkt. This is not included in the flow chart so I doubt it has an effect on 61. I think in theory this MAP is the only way the ECM gets to "see" what the vacuum in the 2* system is because I think the solenoid is only a two wire connection. Therefore there is no reference signal back to ECM.

Wiring. Outside shot is wiring preventing any communication among the solenoid & ECM. I would think you could see damaged wire but who knows.

What I did because of lack of the proper software was to r&r the 2* solenoid and reassemble. DTC 61 re-set, so I knew it was the ECM in my case as I could not find anything else while I was under the plenum using a test light and my Mark1 eyeball.:redface:

Do you have a spare good 2* solenoid? ECM? I have spare solenoids, but used my last ECM on my repair.

E-bay sometimes has Tech1 & Tech1A's listed but the trick is to get the right software. They have a web site, Vertronix.

:cheers:
Tom

Re: acelleration problem?
 

hi all, i believe we have ruled out everything but the ecm. who has the best deal on replacement ecm,thank, Harold

Re: acelleration problem?
 

For a remaned unit (with a warranty) check with your local Chevy dealer.
I bought one last year for $134 plus overnight shipping charges.
I've got the part number here somwhere.....

Re: acelleration problem?
 

GM part #: 16196394

Re: acelleration problem?
 

Kurt's got a few NOS still on the shelf if you're a NCRS kind of guy, but be prepared to spend an arm and a leg and you'll probably have to toss in your first born as well to seal the deal.

Re: acelleration problem?
 

Who is Kurt, and how bad is he going to hurt me?Harold

Re: acelleration problem?
 

Kurt White of White Racing Products.
http://www.whiteracingproducts.com/home

He is "Miura Parts" on eBay.

Figure on spending $450 or so.