# 1991 Maxima SE No power in lower half of RPM range



## Gymbo (May 18, 2008)

Long time lurker....occasional poster....

I have a 1991 Maxima SE auto transmission with a little over 250K on it. It runs a little rough in general but until the last two days drives well. But now it has little to no power when it gets warmed up...after driving it for 15 minutes or so. If it's below 2500 RPM I can floor it and it does almost nothing. Once I get the RPMs up in the 2500 (or better yet 3000) and above it has decent power. I put a fuel pressure gauge on it yesterday per the Nissan service manual and it read 36psi and comes right up to mid-40s when the throttle is opened. With no load it does have a bit of a miss just off idle, but runs pretty smooth at 2500 and above. I do have injectors on order....pretty sure I have 1, maybe 2 bad injectors. But it ran pretty ok until yesterday....I am wondering could it be the COIL? Because the it acted up with the fuel tank down around 1/4 tank I am also wondering if it could be FUEL PUMP giving out when it gets hot?

Any insight would be greatly appreciated.

Thanks
Jim


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## Gymbo (May 18, 2008)

I should also add......that I have noticed that it has seemed to have more power in the mornings, especially cool ones....and less power after work when the temps are up. 

If that helps.

Thanks again.
Jim


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## Gymbo (May 18, 2008)

Problem resolved. Just to give an update....had two injectors replaced and 4 injector harnesses rebuilt.....runs much better. Only a slight rough idle once it gets really warm. I am going to start a new topic asking about opinions about that.


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