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Discussion Starter · #1 ·
Sorry if I'm over posting here...just that my new (to me) '88 has a bunch of issues to work through and I'm not finding a ton of data with the search funtion.

Basically, my question is, what is the correct warm up regulator for an '88 Esprit? My '88 has a 0438140014 installed in it and it looks pretty tired. The car idles a bit rough when cold.

I've seen a website reference to a 0438140096 for the 1988 Esprit - that site (www.specialtauto.om) being a site purporting to rebuild WURs...so I would hope they know which is the right one.

Anybody have any idea what's the right WUR for an '88?

Thanks
 

· Cal H
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Lotus part A910E6732F=Bosch 0438140 096 last 3 numbers designate different calibrations for individual model of cars that use the K-Jetronic. A lot of people use the 1st 8 numbers for this part and self calibrate the unit. Ebay has a whole bunch on sale. unfortunately I have the Delco or I would know how to do this. I bet Robert knows as he used to be a Volvo mechanic and they use the same CIS. So I will turn you over to the expert

http://www.ebay.com/sch/i.html?_odk...gulator&_nkw=Bosch+Warm+Up+Regulator&_sacat=0

Have you tried to adjust the unit? Here is the instructions to test and adjust the unit. Need to find the calibration numbers for the Esprit.
http://www.benzworld.org/forums/w126-s-se-sec-sel-sd/1372083-warm-up-regulator-wur-calibration.html

http://www.landsharkoz.com/images/pdf/wurfix.pdf
 

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Discussion Starter · #3 ·
Thanks Cal. I guess perhaps my '88 has the wrong WUR in it if ...096 is the correct one.

I realize it's possible to work with different WURs to try to achieve the right AFR, and I have done that here and there. I have a pretty sizable collection of WURs for porsche and ferrari. And, I realize it's possible to "tune" an individual WUR as well, but have steered away from doing that in preference to getting the right WUR, working properly.

There's a lot of used WURs floating around out there with dead heat sensor and bad bimetallic arms....most old/used WURs have some problem in my experience. Once in a while you find a new/OEM one which is right for the application and that's pretty nice. I'll look around for a new or rebuilt 096 and start with that.

Thanks again!
 

· Cal H
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I'm pretty sure all the Esprit's equipped Bosch CIS used the same WUR. Some people do use different WUR to custom tune as there is a vac port that affect enrichment after warm up but I think to make it work right you have to change injectors and some other things, this is what I have heard during casual conversation though. Purportedly the 1981-86 Peugeot 505i uses the same WUR 096 calibration found in the Esprit but I have heard of it and the Esprit also using 021 and 026 calibration. It is unknown if some of these WUR have been rebuilt into different cases as there are many places that take old WUR as a core and if they don't take the old number off or if they just stick on a label over the original number that later falls off due to engine heat that adds to the confusion. I think the calibration numbers are like .05 cold and 3.7 warm

This is supposed to be better per a Tim Engel discussion on how to manipulate the Bosch CIS similar to the EFI. Also someone made mention that MRDANGEROUS mentioned this unit too in the past.
UTCIS-V or the more advanced PT
http://unwiredtools.com/utcis.asp#applications

Any owner of a Bosch CIS equipped Esprit that wants a manage and program variable performance condition for the Bosch it appears this is the way to go. Any you 86-88 guys have one of these and what do you think of them?
http://unwiredtools.com/manuals/UTCIS_Application_Guide_A2.pdf

Good luck
 

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X180 WUR

0438140096 search does not yield any results.
Although, 0438140094 is an Audi Turbo boost sensing WUR, which could be plumbed in as an improvement over the OE part.
In your case, I don't see a real need of going with an expensive UTCIS DWUR.
You should not judge any parts by their "looks".
It is much more important if your WUR provides the correct cold/hot control pressure.
Spec is 2.1-2.4 bar cold, 3.45-4.0 bar warm.

Also, check all posts by
amanda11270
who has rebuilt his WUR couple of times (2013?)
 

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Fuel pressure is important however the 'plate' surface must be clean of 'gummy' gas. It needs to move smoothly with the plunger controlling the fuel rate. Sometimes the simplest things can cause the biggest problems. By the 'plate' I mean the fuel distributor plenuum plate. Over time it gets a varnish around it and hangs up the plate from moving the fuel plunger freely.

To diagnose a WUR as MR D. said the the cold and warm fuel pressures need to be checked first.

I have written many posts on using a DVOM to read the dwell and correct it. Yes these do go bad and' "Amanda" has some good info.



Robert.
 

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I got about 5 of these from a Junkyard near me from different cars, all non vacuum type, I honestly tried every one and combinations of parts from every one, and they all did the same thing, similar performance, I noticed no difference at all. I did use what looked to be the ones closest to the heater setup as the factory Lotus regulator though. The one on my car when I got it had two heaters in it, all the others I got only had one, but they still seem to do the same thing. I dont even know if mine was bad or not, as I started messing with it before I knew how it even worked. I did find a burnt out heating element in it though and replaced it with a heater from one of my junkyard regulators. I drove with all these regulators for about a week or so also.

I can tell you from experience if you open this can of worms, make yourself an adjustable pin, knocking that thing in too far is a pain, cause then you gotta take it apart, pull it back out, hit it in again. I brazed a threaded shaft into a pin, as I tried twice to drill and tap it, and both my taps broke. And I never had a problem with the pin spinning in the body when adjusting it. A few places on the net talk of making it so it doesnt turn in the body when you adjust the nut to pull the pin back out, so the pin doesnt spin I mean (if this makes sense to you, my pin has a threaded rod brazed in it, then a nut on top of the regulator that when tightened retracts the pin, then I loosen it to hit it back in, very easy to adjust now)

Think my hands hand no feeling for like a month and a half from constantly pulling and changing hot WURs, and working on them when they were still hot from the car. Gas going all over the motor, what a mess that was, its sorted now though, and I got my fingers crossed, I check the fuel pressure with the timing about twice a year now though since I have a much better idea what im doing.
 

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Discussion Starter · #9 ·
Good stuff guys. This really is the same modern-equivalent of messing around with different jets in old weber carbs...

My '88 (bosch CIS) has the 014 WUR and this works pretty well - good idle at cold, doesn't stumble or hesitate when accelerating both cold and hot, good gas economy. I tried an 026 and it seemed to allow marginally stronger throttle response, but the cold idle was horrible.

The 096 is the specified WUR according to www.specialtauto.com...they do a lot of work rebuilding WURs so presumably they have some idea what they're talking about. I haven't tried a 096 so I have no first hand experience with that one.
 

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Although of the cost I only run Super Octane fuel in my Audi S6 and Lotus Esprit. Yes, it cost's more however it's what the engine craves. It's amazing how much varnish and crap I've cleaned out of throttle body's plus fuel injection systems using LOW grade fuel/

If your using an injection system with low grade fuel it plugs the injectors or 'cokes' up the 'butterflies' and shaft pivots. This makes it very sticky and cause them to bind up. When this happens all hell breaks loose and causes your car to act very wierd. Those binding parts add or restrict fuel flow, a point which is alway's overlooked.

Do they still use this system?

Last I knew they had electronic computer fuel injected systems with electronic fuel body's needing factory equipment to get the problem solved. Never a better time to leave the trade and for those thinking about a career doing this.... THINK TWICE!!!

Robert
 

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I have had the UTCIS PT installed for several years.
The ease of installation and removal is fairly important
feature to me as I live in California where the smog restrictions
are pretty stringent. Very easy to create maps for control
pressure. Adjustable at 250 RPM increments. USB cable
runs to the glovebox and Sony VAIO for on the fly adjustments.
Have the car in pieces now with many mods to the Bosch
system and I'll just have to wait and see how it all works
when it's back together.
 

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X180 DWUR

Comment:
"PT" Digital Warm Up Regulator works better with non-OE ignition systems.
If one wants to convert to PT DWUR, I'd suggest ignition upgrade to Pertronix or Megajolt.

UnwiredTools UTCIS-PTâ„¢
.
.
 

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I should rephrase something I stated above about similar performance. For the short period that the car warms, around a minute or so, I did notice different regulators seemed to make the car run slightly smoother, maybe slightly more driveable than others, but you are only talking til it warms up, and mostly my car is coming out of a heated garage, I seldom let it sit out anywhere, especially when its cold out. But once they warm, virtually identical performance. Any of them I could of still used. I went back to the original one, just because. But I swapped a burnt out heater in it from a junkyard one.

When I set my WUR I obviously concentrated more on the warm pressure, than cold start, but then I dont remember having a too difficult time ever starting it.

I pull my plugs and they are always light beige, so it must be almost if not correct.
 
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