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Discussion Starter #1
Got everything back together on the car last weekend. Started with minimal problem and didn't catch on fire! Only leak was the oil supply of the turbo which required a little cleaning of the fitting and a little torque on the nut. Ran it up to operating temperature and bled the cooling system. Went home a happy man.

Buttoned everything up yesterday and went for a drive. Car starting sputtering and missing badly for about the first couple miles. I think it was running way too rich and fouling the plugs. Just when I started to head back, the engine cleared up and ran great the rest of my trip.

Drove it this morning to work and as per yesterday, it started off rough and got worse. Backfired once and I saw flames shoot out the exhaust. Obviously way too much fuel! This wasn't good... Pulled over on the side of the road to look at the motor, didn't see anything unusual. Was getting ready to call AAA for a tow but figured I'd try and start it just for grins. Fired right up and drove perfectly the 9-10 miles to my office.

My thoughts are there's something going on with the cold start circuit, perhaps the WUR.

Anyone have any suggestions about where to start?


Thanks
 

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Cold start valve possibly stuck open? Check to see that it isn't getting any power after the car has started; it should only supply fuel during cold cranking.
 

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Discussion Starter #3
Thanks Mike

I will put that on my list to check. The first thing I'm going to check is fuel pressure to the WUR, both cold and hot.

Wanted to add some more info to the problem.

When I first started the car and brought it up to operating temperature, it rev'd well, no missing. Seems like it's only missing when a load is applied when I first started driving.
 

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Discussion Starter #4
After much research I attempted to measure my fuel pressure today.

Here's what I found

Cold Control Pressure - 2 lbs
Warm Control Pressure - N/A
(By warm control pressure I mean plugging in power to WUR and let it warm up)

Primary Pressure - 90 lbs / 6.2 bar

Something is not right.

I also attempted to measure voltage to the wires going to the WUR and got 0 volts. Measured impedence on WUR and got 10-11.

Could not measure Warm Control Pressure because I had no voltage to WUR.

What am I doing wrong or maybe a better question, where do I begin?

Thanks
 

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Start with the lowest point.....what kind of volts are you getting at the fuel pumps?

Seems like you are starting way upstream.


Also, if I understand everything....did you have your engine out? if so, I would check and clean all of your harness connections.
 

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Discussion Starter #7
I think my fuel pumps are fine sense I'm getting good primary fuel pressure.

I just have a feeling that the WUR is involved in the problem so I'm getting that fixed. Once I know I'm dealing with a good WUR I'll start diagnosing other potential problems.

I've had my car about a year, did have the engine out for 9 months of that period. Really ready to get this fixed but I'm in no hurry.
 

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My best guess would be that the bi-metal actuator in your CIS warm up regulator has died. This usually results in the engine starting just fine when cold but running poorly during warm up which is when this regulator normally enriches the fuel mixture to support cold running. Once the engine reaches operating temperature the warm up regulator is no longer needed and the CIS system runs off of the normal mixture determined by the ECM. On two separate occasions my '86 Esprit started running poorly after cold starts just like yours and each time it was the warm up regulator. Here is a link to another post with more information about this common problem: http://www.lotustalk.com/forums/f16...pm-relay-vacuum-advance-cis-kjetronic-113188/ Of course what makes this whole thing even more frustrating is that your warm up regulator is specific to the Esprit so you cant just swap in one from another CIS equipped car and the last time I checked, new Esprit warm up regulators were not easy to obtain and certainly not cheap when finally found.
 

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Check resistance across the heater contacts, should measure 12-28 ohm. Open loop=junk.
If resistance checks good, WUR may have some deposits or corrosion due to ethanol+stagnant petrol sitting there during non-use period.
Proper CCP & WCP should be as on the diagram below.

Before tearing the unit apart, or replacing it, bang on the side w/small hammer while running the car. See if it'll "fix itself".
 

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