built 7M lacking power

[91Supra313]

So it could very well be a coolant temp sensor...

 

[3p141592654]

That is how it is supposed to work, if the engine gets hot.

 

[Mikael_7m]

well I'm still having this issue with my car.
I replaced a couple of silicon joiners that I thought to be a little worse for wear. Still the same problem, hits set boost of 11psi but revs slow, sounds rough and lacks power.
I haven't change my plugs or leads for a while, could this have any influence? There is no misfiring or breaking up...

 

[satx88supra]

Did you check compression yet? I had kinda the same issue with my built 7M. Ran fine but just seemed....off. Did a compression test and was low on #1 cylinder. Leakdown test points to bad rings or something on lower end. Not trying to give you bad luck but like another poster said....you would want to check compression after a build anyway. Power starts in the combustion chamber.....make sure everything is fine there then move on to the next thing.

 

[Mikael_7m]

Good point. I really don't like to think about compression but ill get it checked :/

 

[shipkiller]

I had the same symptoms before going 1jzgte.
Ended up throwing two rod bearings and found that I had little compression on #5 and none on #6

 

[Mikael_7m]

I had the same symptoms before going 1jzgte.
Ended up throwing two rod bearings and found that I had little compression on #5 and none on #6

this is a built motor on like 600 miles, can't see how compression would be the culprit, but i'll check anyway. Engine builder has built numerous motors mainly RB's.

 

[91Supra313]

this is a built motor on like 600 miles, can't see how compression would be the culprit, but i'll check anyway. Engine builder has built numerous motors mainly RB's.

Shit happens man. He might have had something else on his mind at the time and messed up somewhere. It never hurts to double check what you can.

 

[Mikael_7m]

Dropped a built 7M in not long ago.
Typical build:
reconditioned head
Probe .20 over forged pistons
Eagle rods
Polished crank
Block and head machined
Cometic 1.3mm head gasket

Now the issue is it seems to lack power. It felt quite a bit quicker with the tired old motor!
It had code 51 so I recalibrated the TPS and the code went away. At the moment my car does not throw any codes. I checked timing, vacuum leaks and boost leaks and didn't find anything obvious. Maybe I need to double check for boost leaks.
It still hits the boost that I set it to (11 psi), but just feels and sounds like its working so hard and not really goin anywhere.

Any ideas or tips guys?

So I thought I'd let everyone know I solved this issue! Had been driving me insane for too long! When I recalibrated the TPS back then, little did I know that it was sticking slightly open when idling and so I went and re-adjusted the throttle stop, and it was all good. I made the mistake of not checking the timing once more. So my car was hitting the boost I set it too except I could feel something wasn't right.

Everybody was like, maybe you expect too much, maybe the compressions low, maybe maybe...

Checked the timing again this morning and it was below 0 degrees at idle. So I set it to 10 and it now drives like a dream!

Sorry for the long rant, just filled with joy right now!

 

[7M4EVR]

Well I'm glad you got it running good. And we were just throwing ideas out there to help... if u read ur first post u said u recalibrated the tps and checked timing so were not gonna immediately tell u to go check ur tps or timing, right?

 

[IndigoMKII]

when you say you checked timing, do you mean mechanical or electrical?

this could of fixed your problem a long time ago. glad you fixed it though

 

[3p141592654]

You should read up on code 51 Would have diagnosed your problem in 30 seconds.

 

[Mikael_7m]

After reading my post I see how I may have come across like a prick. Was not my intentions. I appreciated the help/advice!

My mistake was I failed to check the timing once I got the throttle to fully close, something I over looked.