found this about rough start

Hi I just found this someone told to to look for it!
thanks to that person!!

I felt It should be moved up here so others would find it!
many thanks to the person that did post this!!!
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Sparkman
Forum User Join Date: May 2004
Location: Western, NY
Posts: 177

Re: XJ misses out after it warms up on restart

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Fuel System - Hot Start Misfire/MIL ON/DTC's/Rough Idle
NUMBER: 18-031-03

SYMPTOM/CONDITION:

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 (90°F) 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.

REPAIR PROCEDURE:
1. Cut insulator sleeve, p/n 56028371AA, to make two (2) insulator sleeves about 25-30 mm (1 in.) in length.

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).

Thanks, I had forgotten about that TSB. It never hurts to read the destructions :laugh3:

IIRC this applies to the distributorless setup

Awesome post! I am just now starting to experience this w/my wife's 2k. It acts just like it's described. Thanks Lenny! :wave:

hate digging up old threads but I have this exact condition on my 89.This heat soak problem only applies to newer xj's?
anyone have a source for the injector sleeve besides the dealer?I'm going to install it on the #3 injector to see if it cures my problem...

only does it once in a great while and does it in cold weather or hot.....

you can use the same heat sleeves designed for plug boots to insulate your injectors-- most any speed shop or parts store should have 'em.

yea I thought about that.Thanks.

would this stuff work??same problem 89 4.0

how often does yours do it?

yep thats what mine does but only about twice a year.....I guess conditions have to be right for mine to do it.
Do you have the factory exhaust "cookie sheet" heatshield on?

Great thread!

Anyone care to explain cookie sheet heat shield Thx.:eyes:

I also noticed that it only seemed to happen to my XJ (Before I Insulated the injectors) After the switch to 10% ethenol in my area in the fall.
From April to late Oct it never happend, no matter how hard I ran her!

Makes sense as the ethanol will vaporize easier. Essentially you're dealing with vapor lock.

Does it continue to stumble? Our 01 will stumble until you shut it off. You can immediately restart it and it runs fine. Its done it twice now in the last 2-3 months.

Heat soak issue is when you restart a hot motor. You are saying it runs fine when restarted. When does it stumble?

Mine does it every time the engine is hot and I restart in under 30 min. I insulated the # 3 and it didn't help....

When you think about it, the heat comes out of the motor and the insulation seems bogus. Some people have reported mostly solving this problem by adding a manual switch to the efan with a timer to auto shut off.