My RPM does not drop nor car stalls its just when i have AC On and shift, it feels like someone who just started driving manual car and does not know how to shift, thats how bad it jurks when shifting , when AC off car feels normal.

 

just a regular routine..

 

Ok i did another test today , This time i took all spark plugs out, pulled fuel pump / srs fuse out and I got this results
180
180
180
180
As always try to start the car for 10 sec on each test and had gas pedal at WOT and car was hot.

My concern is why my conpression is so low. Lower then factory specs suppose to be 250 psi/

And why i had 150 on first piston, 170 on 2nd, 170 on 3rd, and 180 on 4th the other day and today i got same reading for all pistons , but still way too low for facroty specifications
\Any ideal what this might be????

 

It may sound silly , but perhaps the compression gauge is a pile of shit . Find a different gauge and retest .

 

Seconded. I can't imagine you having 150psi in one of the cylinders and your car not running like crap. Retest looks quite a bit better. Does the car pull hard and run smoothly? AC sucking up power and making the car difficult to drive i quite normal on this, and most 4cyl cars. As importkid mentioned heat soak (especially this time of year) can be quite noticeable at lower speeds around town as well.

 

your motor must be dead cold before you do compression test, that is what my mehanic told me

 

No engine should be hot for compression tests to give a correct reading.

 

I WOULD NOT RETURN TO THAT MECHANIC.

 

Sorry guys for making this thread to live again.
this is the same user that posted original post.
after all this time i drove my car still have no issues with motor, need to replace my transmission ASAP.

Also anyone has any idea why my compression is at 180 on all cylinders
Could it be that someone modded internals? like pistons to lower compression?
thanks in advance.

 

Use a different compression tester and see if it still reads low in every cylinder.