Please Help! Intermittent problem after cranking
 

Ok guys, I need some help with an Intermittent problem that I am having with my '91 n/a 'Vert. The following has happened twice in the past month and then twice yesterday and I'm worried I may get starnded somewhere.

Heres what happens:

On a hot day, after I have driven 15 or 20 miles and the car is good and hot, running great, I will stop somewhere for 15-45 minutes. When I return to the car, it starts fine and idles fine but when I hit 1800rpm it dies back to idle. I can floor it and will just pulsate between 1800 and idle. I'll let it idle, poke around under the hood scratching my head and then several minutes later it returns to normal and I'm on my way.

It happens exactly this way everytime. Does this sound familiar to anyone?


I'm not sure if this is related: a few months ago, while putting in a new alternator, accidently I broke one of the little plastic nipples that has a little upside down "U" shaped vaccum hose attached to it just to the right of the alternator. I just tried to tape it back on. I'm not sure what the purpose of those "U" shaped vaccum hoses are but it didnt seem to affect the running of the car at the time.

OK, it appears that the lower plunger on the Throttle Position Sensor(TPS) is getting stuck a bit less than half way out as I am pressing the gas. I sprayed some WD40 on it and it seems to move in and out much better.

1)Am I on the right track?
2)Has this happened to anyone else?
3)Why does this happen?
4)Is there any reason I shouldnt use WD40 on those moving plastic parts.
5)Is there any thing else I should do?

Thanks!!!!!