Vapor lock while driving?

I went on a light trail ride with a few friends yesterday. I was going up a fire road in 4hi at around ~5mph. My xj was running slightly over 210. The e-fan was on. All the sudden it started to loose all power and sputter then stalled. I tried to start it right after and now luck. It tried to run but stalled. I let it cool off for about 5 mins and it started up with no problems. Is vapor lock causing this?

93 XJ
4.0L
AW4
3" lift 31's

shouldn't see vapor lock in a fuel injected vehicle while it's running. The system is under constant pressure (keeping it from boiling)

I'd say the fuel pump overheated or you stirred up a bunch of junk in the tank and stopped up the filters (in tank or in line)

I have never ran into this issue before and this was very light wheeling. I will change my fuel filter since I am sure it needs to be done. But good point about the over heating fuel pump.

Let's see, high temperatures and Environmental Nazi gasoline. Yes, its vapor lock.

Tim_MN said:

Let's see, high temperatures and Environmental Nazi gasoline. Yes, its vapor lock.

Click to expand...

I agree Cali gas is horrible. My 350z hates 91 gas on a hot day.

It was close to 90 and a little more humid than usual. I am guessing we were around 3500ft in elevation.

Well, Gertie, hang onto your drawers--EPA wants to go 15 percent ethanol.

OP--could be early signs of a thermal failure in the crank sensor.

A**uming the usual 50/50 ethylene glycol and distilled water mix? That is the perfect limp d*ck compromise for year round driving. Ethylene glycol is an excellent anti-freeze. As for cooling, it sucks. Change your coolant mix to 30 ethylene glycol and 70 distilled water for Summer driving, switch back to 50/50 in the late Fall.

Number 3 injector heat soak TSB but this is for later models than your 93


Quote:
1803103 - 4.0L ROUGH ENGINE IDLE AFTER RESTART FOLLOWING A HOT SOAK
Date: 09/05/03 (supercedes 1802702 dated 09/06/02)
Model Year(s): 1999-2004

Description: NOTE: This bulletin applies to vehicles equipped with a 4.0L engine. This bulletin involves the installation of a fuel injector insulator sleeve.

Details: Customers may describe a 20 to 30 second rough idle following the restart of a heat soaked engine. This condition may be most noticeable when the engine is restarted following a prior 10 to 20 minute heat soak in hot ambient conditions of approximately 32 C (90ºF) or higher. This condition may be consistent with short city stop-and-go driving trips and can be aggravated by the use of fuel with a high ethanol content. Depending upon various conditions a MIL may occur due to DTC P0303 - Cylinder #3 Misfire.

This condition may be caused by heat from the exhaust manifold that following engine shut down migrates to the area around injector #3 and causes fuel vapor to form within the injector. This in turn may cause a momentary misfire of cylinder #3 until the fuel vapor is cleared of injector #3. The insulator sleeve lowers the injector #3 temperature to a point below which the fuel will not normally vaporize.

If vehicle exhibits a rough idle, and if a misfire of cylinder #3 is observed following a 10 to 20 minute hot soak, perform the Repair Procedure.

Parts required:
56028371AA Ignition Wire Shield

Repair procedure:
1. Cut insulator sleeve, p/n 56028371AA, to make two (2) insulator sleeves about 25-30 mm (1 in.) in length. See diagram.
2. Install one sleeve around injector #3, with the slit on the upward facing side of the injector. Install the other sleeve with the slit on the downward facing side of the injector.
3. Confirm sleeve is flush to intake manifold surface around injector.
4. Check injector #3 wire and ensure that the injector is rotated to a 2 o'clock position (from driver’s side of vehicle).

That TSB is not related to his problem. Wrong year, wrong circumstances.

joe_peters said:

Well, Gertie, hang onto your drawers--EPA wants to go 15 percent ethanol.

OP--could be early signs of a thermal failure in the crank sensor.

A**uming the usual 50/50 ethylene glycol and distilled water mix? That is the perfect limp d*ck compromise for year round driving. Ethylene glycol is an excellent anti-freeze. As for cooling, it sucks. Change your coolant mix to 30 ethylene glycol and 70 distilled water for Summer driving, switch back to 50/50 in the late Fall.

Click to expand...

I just logged on to post that after hours of reading threads on a few boards. It sounds like it could be my crank sensor.

I also bought a new radiator and WP a few weeks ago but have not had the chance to put them in.

So I drove the jeep a bit this weeking around town. It start like normal (couple cranks).
The jeep got to normal op temps before I stopped at a store. When I came out it took more cranks than usual for it to start. So I am really thinking it is the CPS.