Hi everybody. I'm new here and a newbie to old trucks. I just bought an '87 Scottsdale. I want to restore it but right now I'm just trying to get it to run decently. It stalls out when I put it in reverse or drive. I looked under the hood and this part is broken. It had a rod hooked up to that was attached to a throttle bracket or something (Please forgive me I'm not super knowledgeable yet). I went to the parts store and showed them the picture and they had no clue what it was. They looked through the books but couldn't find it. Any ideas about what this part is?
RE: What is it? It very much like an emissions control valve I've seen on 70's era cars. Can you pan back on the picture and do you have a vacume digram on your core support this may have the item listed on it. also look at the exhaust manifold between the cast iron manifold and the pipe, is there a disk valve(a piece of cast steel between the two pieces with a loose arm or carroded tab there, this could be part of the pre-heat system. this could be a retro fit emission up grade. sorry about the spelling. also another way is does your are require emissions inspections if so a good inspector will or should know if it is part of the system. keep in touch my 88 suburban doesn't have this, mine has a/c does yours
Do you think that this might be what is making it stall out? Somebody I was talking to said I should replace the throttle body gasket. I looked at it and it looks rotten.
That's part of the cruise control system. Its a vacuum actuator that holds the throttle open when the cruise control is active. My diesel parts truck had cruise, but I pulled it all and left it in a box on the shelf and capped the vacuum line that supplied it. (more trouble than its worth IMO) Unless one of the vacuum lines running to it are damaged, I don't believe that is causing the problem. If your throttle body gasket is rotting, that is a more likely culprit.
I changed out the throttle body gasket last night. It didn't look as bad as I thought it would be. My truck is still stalling so I'm guessing it's a vacuum leak somewhere. Does anybody have a good way to detect vacuum leaks?
Try W/D 40 around the intakes seals if your get a higher rev with the motor running you got a leak. And any fitting on the intake. one at a time. For the vacuum lines un plug one at a time plug both side see if it has any effect on the running motor then re-hook up and try the next one. and if you see any that break or cracked change them.
