Engine Loading in gear

[blacknight80]

Hey guys first drive since it's been running and I've got some shit to sort out. My idle when cold is wild....revs up to 1300 briefly and drops down to near stalling. Once it warms up the idle normalized and after it's at full operating temp for a while it idles up and stays there. Then when I drop it in gear it loads up and my vac goes from 20 to 5 as if im brake torqueing. I have to stand on the brakes to hold it back. My scan tool was acting up so I didn't get any readings. Any ideas on what I should try? The ecm has an old hyper tech chip if that .akes any difference. I have everything to do the 87 ecm swap but I don't want to compound any issues by slapping more parts on.

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[bpman1234]

So first thing check for vacuum leaks dry rotted hose ect.that vacuum blocks is known to leak and maybe cracked. then how old is the fuel pump? Also with my hot air my alternator would go from 14.5 volts to 17 volts when it got hot and it would load up at idle .is the maf original ?also go to the ecm and take the chip out look for corrosion. Then put it all back see what happens.

 

[blacknight80]

All the vac lines are new. I'll propane check the vac block. What are our options for replacing it, do the ic ones work? Brand new racetronix pump hotwored. Brand new 140 amp alt. Maf is original and it will go when I swap the ecm. Maybe I'll just do the swap and see what happens

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[bpman1234]

The after market vacuum blocks are aluminum and you can get one from one of the vendors on the board the ic ones are different. you have a shop vac that pushes air you can blow it through the intake pipe just make sure your getting clean air .spray watered down dish washing liquid on all the hose from the vac block to where ever they all go and the new one's to open the butterfly and looks for bubbles. Also spay the whole vacuum block and intake plenum. See what happens

 

[blacknight80]

Thanks I'll try that. I magically lost oil pressure yesterday too so this might all be for nothing [emoji26] thanks for the help this car wouldn't be running without the help of everyone on the board

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[bpman1234]

Yeah know the feeling. My 87 would of had my 455 Olds rocket big block in it long time ago .

 

[blacknight80]

Well I went out and fiddled with it today and it wouldn't do what it did yesterday (and every day since it's been running again) [emoji36]....typical.