Can you compression test with Factory ECU on a single turbo setup?
 

I was going to run a compression test on a basically new engine (5k on rebuild from reputable community rebuilder). Howevever, I sold the PowerFC and I was wondering if it is safe to run a live compression test with a Single turbo and upgraded fuel system using the factory ECU (only for the test and to move it in very low rpms out of the garage?)

Any wizards would be appreciated!

yes, as long as you dont boost and its not drastically ported

It will probably run like crap but if you are just driving the car 20-40 feet it wont be an issue, I wouldnt drive up the road with that setup.

David

you will most likely be immediately put into limp mode since you don't have your solinoids hooked up anymore anyways, so i wouldn't worry about boosting. u may also want to just do the compression test before you start it up since having an upgraded fuel system with a stock ECU could potentially flood out the engine and cause you to lose compression.

Since you said, upgraded fuel system... if you have 850's in the primary's or any other larger then stock injector, be sure to give it a rev before you turn it off to blow all the excess gas out of the engine so it starts up again.

Thanks for the replies. Will give it a go :)

Compression test = Yes.
Driving/moving = No.

Since the EGI is removed during the compression test, your upgraded fuel system won't matter. However, actually starting the car is not a good idea and I don't recommend it.

You can do a compression test cold, but the numbers will be slightly off. Still, you can use it to get a general idea on the condition of the motor.