Renix random engine cranking without starting problem .... SOLVED!!!!

Yep, and it had bugged me for a couple months now: I'd try to start my 89 XJ with the (numerous expletives considered but not said) Renix MFI and it
would crank fine but no start.
Always before it would start up after I'd (A) moved the vehicle out of a parking stall in case I needed a tow/jump, (B) slammed the hood ( I have a liftgate cylinder helping prop it open and for lifting it), or (C) slammed the door.
And I was always in a moderately high noise area, i.e. parking lots.
But this last Tuesday, it happened in my driveway in a nice quiet area of town.
And I noticed there was no fuel pump noises.
Pump has less that 10,000 miles on it, btw.
So I bled the rail and no noise.
Fuses were all ok so I suspected the pump relay as I had some spare relays from a 92 XJ I'd scrapped out. Popped in a relay with less than 300K miles on it and now it starts faster and the pump sounds healthier and a random idle rpm miss I had has dissapeared..
So ... if your Renix MFI system acts weird with no starts and there is no pump noise, I suggest carrying a spare relay or two.
--
Budd

" I looked into an exercise plan at a local gym but they didn't
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Budd Cochran wrote:

Those dang relays cause all sorts of problems. Usually you can trade AC/Fog/Fuel relays.
My first suggestion if you can't hear the pump is to just bypass the relay. It's also the easiest way to test for pressure on the rail without having the engine running. A vac pump can then fool the pressure regulator to kick in and give you idle vs. wot pressures.
--
DougW



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Ok, I will print that out because I didn't know I could test it that way.
I'm also looking at doing an R&R on my cam and lifters because the lifters on #3 have decided to collapse (ticking noise in vlve cover).
Makes the idea I had of swapping a carbed 258 with torq-command sound better and better ... and my older brother has this old Eagle wagon sitting in his driveway . . . . . . . .if only the T-case will swap
--
Budd

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Budd Cochran wrote:

A weak oil pump can do that too. 32 psi on the I6
Worn valve guides.
Other tick (the one I have) is a itty bitty hole in the exhaust gasket. (I'm just to damn lazy to fix it)

JEEP Just Empty Every Pocket
--
DougW



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I have 40+ psi at any rpm over 1000 and 35 at idle (20W-50 oil/ summer, 10W-40/winter ... I like thicker oil on 300,000 plus engines), so rods and mains are still pretty good

Unlike so many renix engines, my airfilter stays pretty dry (little oil on paper) and sloppy guides cause more seal wear resulting in exhaust smoke and/or oil on the filter from leaking exhaust vaporizing valve cover oil. Just eyeballing with a timing light after pulling the cover, those rockers don't lift quite as high as the others.

A mechanic's stethescope zeroes the noise to the valve train but I need to do a check on the manifold also.

Yep, and I thought the A604 trans issues my 95 Lebaron GT convert had were too expensive to be worth fixing . . .
--
Budd

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