if i was getting 150 across the board 2 days ago on all 4 cylinders and all the car has done is sit in the driveway and started 3-5 times over a few days but cylinder 1 is not working, its getting fire, not sure on fuel so i swap injectors between 1 and 2 and now cylinder 1 & 2 are not firing, shop tells me that cylinder 2 has no compression..could i have not seated the injector good enough to cause a low compression reading?

 

Your injectors go into the intake manifold and have nothing to do with compression.

 

You said they were 150 across the board and they say you are loosing compression. What were the shops results across all 4 cylinders?

To answer your initial question...No. Injectors do not have anything to to with a compression test.

 

diagnose the injectors. Sounds like the shop might be BSing you.

 

wait.... out of curiosity, if u were doin ur own comp tests, y did u have a shop do them after?

 

They did there compression test as a part of the diagnostics, its just so weird how i can have cylinder 1 not working, i swap injectors and now the shop says cylinder 2 has no compression, even after i did my own tests and all 4 cylinders had good compression days ago... i am stumped...

I am getting the car towed back to my house today, and ill do another compression test, the shop said i had like 2.5psi on cylinder 2 WTF?

what could cause a cylinder to go from 150 to zero in a few days without even running it much?

 

Could have dropped something into the injector port, getting stuck between the valve and seat. Its possible.

 

It is impossible to have ZERO compression in a cylinder. I don't care how ****ed up it is. Run your own compression test again.

The only way you MIGHT get zero compression is if your valves are sticking in that cylinder. Even if the rings were no good, you would still make a little compression.

Like it has already been stated, injectors have nothing to do with compression.

It sounds like the shop is trying to weasel you into a very expensive rebuild.

Run your own comp test man.

 

UPDATE: car is now firing on all four cylinders, the shop must of messed up on doing a compression test (retards), when i swapped injector 1 and 2 i did not get a good connection between the injector on #2 and the plugin part, so in summary...


Here is what I have learned from this.

-dont reli on shop tests as the end all be all
-trust your own common sense when working on a car.
-fuel injectors can be cleaned using fuel injector cleaner (by submerging the tip of the injector in the cleaning fluid)

Thanks to eveyone who tried to help.

Jason

 

[QUOTE=aasarsak;38713211]It is impossible to have ZERO compression in a cylinder. I don't care how ****ed up it is. Run your own compression test again.

The only way you MIGHT get zero compression is if your valves are sticking in that cylinder. Even if the rings were no good, you would still make a little compression.

QUOTE]

zero is not that uncommon, but on more severly damaged motors. but for 2.5 to even show up on a compression tester definately sounds like b.s.!!!

 

Most important thing IMO.... You learned something, which means (hopefully) you won't repeat it.

I'm glad you listed this as #1. The only reason I take my car to a shop is for welding. I don't know how to do it and I don't have the equipment. I have taught myself how to do everything else. Just did my first motor swap last weekend. It fired up on the first try. I'm not trying to brag, but I'm just giving you an example that you don't have to be ASE certified to know how to work on cars. Just some simple reading and common sense is all you need. I never take my car to a shop for any reason whatsoever with the rare exception of welding (exhaust). My cousin is a mechanic at a dealership and the things he says the shop manager tells the mechanics to do..... [/quote]


Yes.

You're welcome. Good luck in the future.