91 4.0 Too many cranks to start?????

[Satern]

I have a 91 Cherokee with the 4.0 , Automatic. It has 140K mils, I ahve replaced the TPS, Temp Sensor, Map Sensor. The engine takes so long to start. It cranks about 5 times before the engine starts. It does this both warm and cold. Also, The idle when cold is very low, almost stalls. And when its hot it idles over 1K. Any ideas? Thanks for any input.

[gixxer1000]

I have the exact same problem with my 90' Cherokee...has anyone solved this one yet?

[tanno]

Have you replaced the IAC valve?

[88Jeepster]

How about the EGR valve?

[gixxer1000]

Yep.
I found the problem. Fuel pressure was dropping off as soon as I shut off the vehicle. I found the problem to be the hose clamps between the fuel pump and sending unit. They were loose so I tightened them up and the problem is fixed.

[tanno]

Wow, I'd've never expected that one. I have an 88 and those clamps haven't come loose yet.

[seanpeek]

For the other guy with the same problem,

It is rare that you are having the same issue. I would look at you fuel pump though. It might be going out.

[tanno]

Or just check all fuel connections....maybe replace the o-rings for the rail connections.

[95xjsport]

I guess it must be a jeep thing, I have a 95 cherokee with 152000 miles and I have the same problem

[tanno]

Now, cranking 5 times, you mean that's about the number of rotations of the engine or 5 different attempts at starting?

The long starts are common with the 4.0L's.

I was going to attempt to dive into that one, but it's really not a problem. My 88 XJ has 230,000 and still going.

I was going to start with installing an aftermarket ignition system. But other than that, change the motor to a Chevy V-8. I own a 400c.i. that starts in less than one revolution of cranking. I would LOVE my 4.0 to start that quick!

[tanno]

I found this at http:\\www.bc4x4.com about the 4.0L long starts:

"I hate vehicles that take a long time to start. Here's what
I do to avoid this common problem with Jeeps.

Get good plug wires. I use Jacobs since they have one of the
lowest resistance ratings for suppressor wires. I also use a
solid core coil wire to insure full voltage & current at the
distributor.

Get a high quality cap & rotor. Any brand with brass
terminals should be OK.

Use good plugs. I was using Bosch Platinums but recently
switched to Champion truck plugs since they look so pretty
:-)

Replace your fuel filter and the in tank fuel strainer. Most
people don't even know about the strainer or sock in the
tank. If you have more than 50,000 miles, "just do it."

Clean injectors at the fuel rail every year. Summit Racing
sells the Sutton injector cleaner hose for GM vehicles which
fits the 4.0L fuel rail. The cans are available at NAPA for
around $7.00. You attach the can to the rail, disconnect the
pump and pressure regulator vaccuum reference, (to minimize
return to the tank,) and the vehicle runs exclusively on the
cleaner for up to 15 minutes. It's a good idea to vary RPM
and turn it off to allow for some soak time.

Clean the throtle body, including the IAC passage. This
means above and below the throttle plate and the bypass air
passages that are used to control idle speed.

- J e r r y

There is nothing wrong with the 3-5 seconds to start. That
is the amount of time that the sensor on the crank needs to
send info to the computer to be able ignite the fuel. You
should also notice that there is a high rush of rpm
immediately when started, then drops down to idle. This is
standard to the 4.0l engines. Take the money and spend it on
the upgrade of wires, cap, rotor and plugs. No need to
replace the coil.

Michael J Moran"

I'll try to find more if I can, but I think this clears it up.

[bmwilson]

my 89 4.0 had the same issue. Replacement of the crank sensor cured mine, yet first just try to clean the connection located top rear of engine.