Is it a Jeep Thing?

Cherokeekid88 · Oct 22, 2005

When i go to start up my jeep( 88 laredo ), it takes like 2-3 seconds for it to actually starts, and ive noticed my friends Grand Cherokee starts right up, and others people cherokees that i know, they all just start right up, and was wondering if there is a problem and what it is or could be.

Thanks.

the_bandit87 · Oct 22, 2005

My 87 cherokee is the same way, but most of the old RENIX engines I hear start up like that. I'm not positive but I think it either has somthing to do with the origional (Mitsubishi in this case and I think for all early 4.0s) or possible that the Renix sensors and computers take a while to find out what is going on. I've noticed though, if you prime the fuel pump a few times (turn ignition from Off to ON). You can get a slightly faster start out of it.

GSequoia · Oct 22, 2005

Common for Cherokees to take a bit of work to start. I've found that if I let the fuel pump spool up first it starts faster (key the ignition on until the fuel pump stops making noise then continue to start).

Sequoia

langer1 · Oct 22, 2005

That’s normal for a 87.
The Renix system re-calculates timing on every startup.
This takes at least 3 full revolutions of the crank before the injectors are fired.

XJ Buzzard · Oct 22, 2005

My 90 XJ does the same thing. It doesn't start near as quickly as my 92 (which doesn't start quickly either)

chris

MyJeepXJ · Oct 22, 2005

'93 4.Oh HO here... Same thing, about 1 - 2 seconds before its running. It dont matter that much to me, it fires up every time, and thats what counts to me!!

HTH..
Andrew

the_bandit87 · Oct 22, 2005

I've seen the same thing on Post-97 XJs, so I'm not sure. All the Renixs I've seen are like that though.

zfinger · Oct 22, 2005

My 97' was doing it untill I replaced the starter. Maybe clean the connections to the starter, and let the fuel pump kick on before you crank it over.

Or just say screw it cuz it starts either way

langer1 · Oct 23, 2005

zfinger said:
My 97' was doing it untill I replaced the starter. Maybe clean the connections to the starter, and let the fuel pump kick on before you crank it over.

Or just say screw it cuz it starts either way

Good point a bad slow turning starter will make a big differance.
It still takes three turns to set the computer, but the faster the better.

jeepinandy · Oct 23, 2005

I've notice my friends 90 cranks over a few times before starting...

kg4bet · Oct 23, 2005

The only XJ that I have that starts first turn is the 86 and that because it's a 2.8 Chevy.
The 87 and 91 both take two to three turns before they start.

73's KG4BET

andrew2516 · Oct 23, 2005

Yeah, my 93 4.0 H.O starts in about 3 cranks. I notice if you try starting it on a steap hill with the front end up, it takes like 6 or 7 carnks.

old_man · Oct 23, 2005

The reason it takes a second or two to start lies in the ECU figuring out what cylinder to fire and when. It has to do several rotations of the engine before it syncronizes the CPS pulses with the cam sensor pulses.

Slower starting yet can be caused by the fuel pump pressurizing the injectors.

In all reality, it is a good thing. It gives the oil pump a chance to get at least a little oil into the crank and rod bearings before things fire up. It is probably one of the contributing factors to getting 200K+ on a 4.0L.

Is it a Jeep Thing?

Cherokeekid88

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the_bandit87

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GSequoia

Everyone says I'm a jerk.

langer1

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XJ Buzzard

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MyJeepXJ

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the_bandit87

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zfinger

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langer1

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jeepinandy

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kg4bet

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