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Hi. This ranger wont go past 3000 rpm, acts like hitting rev limiter.

Has new plugs, wires. good compression across all cylinders.

Where to start?

what is the exhaust back pressure?

Also what is fuel pressure and flow? Is this free rev or in gear?

backpressure 0 psi both banks, fuel pressure is 60psi at idle, 50 koeo. As for volume, i cannot say. Noticed engine vaccum less than 15 in/hg at idle. fuel injectors were replaced recently, as was fuel filter.

maybe clogged cat?

Check fuel pressure at 3000 rpm. 15 inchs vacuum at idle is low. I have had cars that had presure but not enuff volume to run at higher rpm.

I agree with Jeff. 15 is too low. Find out why.

Scope your cam pos sensor on top of the synchronizer. I had one that did the same thing. Drove me nuts.

The cam position sensor is working normal, we just tried a new one... not sure yet on engine vaccum issue. I noticed something else, fuel trim and o2 sensor readings are what outta wack. bank 1 averaging towards lean o2 reading, fuel trim in positive between 6-9%. bank 2 however is averaging 0.9v on o2, fuel trim keeps going negative, yet will just to shft2 +50%.

i've seen bent tail pipes cause issues. is it an immediate issue or does it take time to build up? if timing has jumped there's your issue.

Id be looking for a vac leak

no vac leak found at all. issue is immediate. exhaust all appeard ok. Best theory was jumped timing as well, jsut due to low vacuum <10inhg. but no way to tell now; cust was tired of truck anyway, sold it i guess. This one had me for a week. I was close to gettin er done but no cigaro..
Im glad its gone but dangit, such a let down for me personally, not to mention the shop. Thanks for the advice and tips!

thanks for keeping us updated.

steven kiser wrote:thanks for keeping us updated.

+1