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Discussion Starter #1
Hi All,
My first post on here (sorry its a long one! ), I'm after some help/advice as I'm running out of ideas on how to fix what I think is an ignition fault on a 1988 N/A HC Stevens Esprit.
I have done various checks and replaced just about everything I can think of; but I still cannot start the car?
So the car has run well for 18 months, then on a run about 10 miles in, it started missing under load uphill, then a mile or so later completely stopped, managed to get it started after 20 mins and limped back and left it, I thought ignition, so changed ht leads to blue ngks, changed spark plugs to spec in book and put a new coil on, it started again okay and I drove 3 miles, put it back thinking resolved. Needed service, so changed fuel filter and checked pump, new oil and filters etc, then took for another spin thinking all good; circa 20 miles later it started missing again, then backfired and stopped, but could not start this time. AA tow home req. AA fella got oscilloscope out and thought ignition amplifier, he also checked rotor arm was turning and thought coil and pick up okay. So at home I checked lead to plug with spark tester, one weak spark when cranking then nothing; so got a new Ign. amp black module from tinternet and no joy, tried re-earthing the AB14 black box direct, nothing; bought an original scrap AB14 amplifier from a Jag, tried that and nothing, also checked engine earth. I then got a new rotor arm and dizzi from SJ Sports cars and still nothing. Checked for a spark from coil ht lead to engine block and couldn't see anything. So I started testing from scratch using Lucas AB14 test card, all good, but ohms rating from dizzy pick up was a little bit high. So I ordered a new pick up from SJ and took the dizzy out, whilst out with the old pick up in, I put the spark tester between 1 lead and plug and turned the dizzy shaft by hand, nice fat spark flash to tester and was getting slightly electrocuted when turning dizzy shaft (with rubber gloves on) so replaced the pick up anyway whilst dizzy was out, added lucas spark shield and new cables back to amp module and still nothing. Tonight I just tried a tester on each plug whilst cranking and I think all 4 seemed to light up at once, but with a very weak spark, then absolutely nothing when continually cranking.
Any thought or ideas would be appreciated. Many Thanks, David.
 

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Wingless Wonder
1988 Esprit Turbo
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5,865 Posts
Hi David,

Welcome to the Esprit section of LotusTalk.


First thought (after a similar recent post) was that the other coils were not matched to the ignition amplifier and overheated, damaging them.

Frenchesprit said:
With my mechanic we tested everything before the last drive test except the ignition coil (just one year used). And during this last drive test when the problem still appears, we change to a used reliable 32C5 ignition coil and the engine then has run perfectly. We discover after the test that the ignition coil which was installed before the test was simply not adapted to the k jetronic with a AB14 ignition amplificator. The ignition coil must be a 32C5 type as the Lucas DLB 198 or equivalent . The former ignition coil was an Bosch equivalent of a DLB 105 which is not a 32C5 type.

+++++++++++

ALSO,
I'm a little unsure of your terminology, but you DID replace the pickup inside the distributor (the one that suffers from broken wires as a result of flexing)?
 

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I second what the wingless one says, its not clear if you replaced the pick up in the distributor, this is a common failure point where the wire is bent and then flexes as the base rotates under vacuum. see pic
lucas-distributor-s3-esprit.jpg
 

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Discussion Starter #4
Hi both thanks for coming back to me. Yep I replaced the pick up and all the wiring; (to be fair the old flex wiring looked okay as well and found a receipt for the old one circa 2005). I also set the pick up air gap correctly.
For info I also tried the old coil back on (which appears genuine Lucas) also disconnecting the rev limiter and presumably rev counter wires that lead to the coil, but nothing. I did check both the new and old coils with the multi meter and they appear to be in range.
However thanks for your suggestion, I think I will try some other spare coils I have, just out of interest, they may work for a short period to get it started. If not I will try and source a genuine new Lucas version. Cheers
 

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Because you are not testing things but just guessing and replacing, you wind up touching a lot of things that were probably not bad but now, because you touched them, have to be suspect because you may have either installed faulty parts or installed them improperly. If you have a no spark condition you don't go replace the HT leads and spark plugs. That won't get you any spark if it isn't coming out of the coil in the first place. Besides possibly bad parts, it is not uncommon to have a bad connection between the parts and you won't find that by replacing parts except by accident. It is time now to check wire by wire and connection by connection, plug by plug and see why you aren't getting spark out of the coil. You have to look really closly, not uncommon for a pin or connector to slide back inside a plug and touch loosely, not actually gripping the other connector in the other plug.
David Teitelbaum
 

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Wingless Wonder
1988 Esprit Turbo
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In addition to what @esprit888 mentioned in Post 3, I've seen broken ignition pickup wires at the two-wire plug that hangs at the right-rear side of the engine bay. I replaced ours (both sides) because it broke (inside the insulation).
 

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Discussion Starter #7
Thanks for the advice guys. Weirdly I just tried the scrap Ignition Amplifier on again with the new distributor pick up\wiring and it fired up straight away. I guess maybe I could have had 1 issue and it turned into 2 from fiddling with stuff, as suggested. Anyway at least I can move the Lotus out of the way and get on with some lock down MG restoration :) thanks for the suggestions 👍
 

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Wingless Wonder
1988 Esprit Turbo
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Just to keep you awake at night o_O



It has been reported here that aftermarket ignition amplifiers have been troublesome, as well.

NEVER throw away parts when you use the Parts Cannon!:giggle:
1262954
 
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