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Low compression

I just put a used transmission in my 02 accord now im having low compression issues what can this be? I never had any issues with the motor before the transmission job.

There is no correlation between your transmission and low engine compression. Did you have a compression check done before the transmission is changed? I have never done a compression check unless a problem arose. Why did you have a compression check done.

Have you checked if the timing belt jumped time or broke?


I’m with @Tester, check the timing belt for the cause of the trouble. Especially if all the cylinders are about the same pressure.

you say you have low compression . . . please elaborate

you have lower than normal compression?

What are the numbers?

Or it won’t start at all?

By the way, are you perhaps just assuming you have low compression? Have you actually verified this?

If Tester is correct, the engine would crank over much faster than normal, but build up 0 compression. That would actually be no compression, not low compression

And if the timing belt is damaged, you may very well have bent valves

It has also occurred to me that your perceived tranny problem might have actually been an engine problem. Knowing why you changed the tranny might provide a clue to your current symptoms. What were the symptoms that cause you to change the tranny?

Well the mechanic that put the trans in is saying that it it isn’t picking up speed properly in the time it is supposed to go 0-60 it’s only getting up to 40mph

Sluggish acceleration could be caused by a ton of different things (poor compression among them). Like TSM said, what led you to get the transmission replaced?

If the mechanic that replaced the transmission is blaming the engine compression for lack of power after changing it and hasn’t even checked the compression yet I would have use a statement the late Tommy would say at times when it was warranted, “the guy is a wacko”. You even stated that you had no engine trouble before the change out. Now a faulty replacement transmission, that is something I would suspect in this case.

“There is no correlation between your transmission and low engine compression.”

I just wanted to repeat that in case the OP missed it.

This whole situation is highly suspect in my opinion. I suspect that the tranny might never have been the problem in the first place, and I also suspect that there are problems with the tranny replacement.

Sadly, I don’t think the guy who replaced the tranny is going to be able to resolve the problem. As a matter of fact, I wouldn’t be surprised if he made the original problem worse by replacing a tranny improperly when it was never even needed. I’d suggest that you take it elsewhere, explain the situation, and let them do s thorough analysis and provide a report to you. Expect to ultimately need to go to small claims court to recoup any of the money already spent.

I think he’s trying to get over on me I talked to him this morning and he said the motor was dying but yet he still hasn’t done the compression test

I know the trans was bad because my girl burnt it up trying to get out of the snow last winter and like I said before I never had any problems with the motor before now

Is the replacement transmission a used one? If so, maybe it’s slipping.

Did the mechanic source the transmission for you? If so and if it’s slipping then maybe he’s trying to lay the blame off on something else rather than have to stand behind the work.

More details would help but it does sound suspect.