Engine Testing

jamesm

Well-Known Member
I'm about to start the process of stripping my donor but I had a question first. The donor that I found has some front end damage and the plastic air intake pieces are all broken. The engine will start up no problem but it will quickly choke itself out as there's no air going through the MAF sensor.

My question is, should I replace the intake pieces and run the engine more?
 

Briann1177

Well-Known Member
From my understanding the engine will run like crap if you have the MAF sensor plugged in and it's not able to get a good reading. My engine will run just fine with no intake plumbing at all and the MAF unplugged.
 

jamesm

Well-Known Member
Hmm..... I may have to dig a little deeper then. I unplugged the sensor but it still does the same basic thing.
 

DanPerryy

Well-Known Member
As I recall mine too ran like crap when I first lit it up. Mine would backfire, not idle, it was a mess. What mine turned out to be is a lot of air in the fuel rail. Purged it and it ran fine.
My post from Dec 2016
"We have ignition Houston!

I completed the installation of my transmission oil cooler, battery cables, and attempted to fire it up. It started immediately, backfired and stopped. A couple more tries the same thing. Then I checked the fuel rail. It was full of air. Bled it and refilled jumpering the fuel pump relay. Hit it again VROOOM - what a kick."
 
Last edited:

jamesm

Well-Known Member
That got it. I pulled the fuel pump relay and started it a couple times, then plugged the relay back in and let the fuel pump run for a couple seconds then started it. It ran pretty rough for 10-15 seconds then settled down to a decent idle. I was able to drive it around a little in the driveway. Clutch feels pretty strong and it drives forward and backwards.

I feel a whole lot better diving into the teardown knowing that it's running.

Thanks again for the tip!
 

DanPerryy

Well-Known Member
As I remember there is a schrader valve on the fuel rail. I bypassed the fuel pump relay with a jumper, keeping the pump running, and then bled the air. I think "bubbles" in the rail will get us.
 
Top