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Discussion Starter #1
Okay, I'm working on this today, figured I could probably get a quick answer out of the larger group. So I've got my new injectors from JAE installed, thanks Jay! Started her up and it ran pretty well for about 10 minutes and then died. Pulled out my Lotus service manual and did some electrical tests. Believing it was the coil, I found one at NAPA, they even had a listing for it which I was a bit surprised with. Put it in, no spark. After a little more diagnosis, it looked to be the ignition switch. Then I realized that in the second position, the fan and dash lights aren't coming on any more, so it's looking like I'm not getting any power to the coil from the ignition switch. The strange thing is that I can jumper the red/brown to the white at the switch and I still don't get power to those accessories or the coil. I've poured through the schematics over and over, but I'm not an EE, so is there something I'm missing? Or is it simply the ignition switch?

Thanks,

Steve
 

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Okay, I'm working on this today, figured I could probably get a quick answer out of the larger group. So I've got my new injectors from JAE installed, thanks Jay! Started her up and it ran pretty well for about 10 minutes and then died. Pulled out my Lotus service manual and did some electrical tests. Believing it was the coil, I found one at NAPA, they even had a listing for it which I was a bit surprised with. Put it in, no spark. After a little more diagnosis, it looked to be the ignition switch. Then I realized that in the second position, the fan and dash lights aren't coming on any more, so it's looking like I'm not getting any power to the coil from the ignition switch. The strange thing is that I can jumper the red/brown to the white at the switch and I still don't get power to those accessories or the coil. I've poured through the schematics over and over, but I'm not an EE, so is there something I'm missing? Or is it simply the ignition switch?

Thanks,

Steve
If it ran for 10 mins and died, it is possible something in the circuit blew a fuse. I'd check that first as it's easy.


Just in case you're correct on the ignition switch - this guy recently parted out an 88 Esprit (only 100 units away from my VIN) and I bought some of his parts - prompt shipment, well packaged, etc:


 

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Discussion Starter #3
If it ran for 10 mins and died, it is possible something in the circuit blew a fuse. I'd check that first as it's easy.


Just in case you're correct on the ignition switch - this guy recently parted out an 88 Esprit (only 100 units away from my VIN) and I bought some of his parts - prompt shipment, well packaged, etc:


I did check all fuses, didn't see anything there. There's a couple of relays in the front compartment, passenger side, that appear to be in the in the circuit, but it's hard to tell for sure from the diagrams. I'm not sure how I'd test those if one is bad. I'm used to having cars I can easily swap parts into, but there's not a lot of Lotus' in the junkyard or around to swap parts with. The trials and tribulations of having a rare 25-year old car. :D

If I can for sure narrow it down to the switch itself, I'd buy this in a minute, I just don't want to throw any more unnecessary parts at it.

Steve
 

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I did check all fuses, didn't see anything there. There's a couple of relays in the front compartment, passenger side, that appear to be in the in the circuit, but it's hard to tell for sure from the diagrams. I'm not sure how I'd test those if one is bad. I'm used to having cars I can easily swap parts into, but there's not a lot of Lotus' in the junkyard or around to swap parts with. The trials and tribulations of having a rare 25-year old car. :D

If I can for sure narrow it down to the switch itself, I'd buy this in a minute, I just don't want to throw any more unnecessary parts at it.

Steve
I hear ya - do you have the 88 driver's hand book that came with the car? It has a diagram of what each relay does. You might be able to get an assistant to put a hand on the suspected relay and turn on ignition to see if the relay is energizing/switching.
 

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I have found lately that most of the relays, and modules in the trunk come apart easily and you can actually see if a relays is pulling in or not, most of the components have a board level relay on them. I actually repaired my faulty RPM relay that had bad solder joints on the tiny relay coil windings causing a no frequency valve issue. It does help to have a helper though turn the key so you can see what is goin on back there when the motors crankin.
 

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1988 Esprit Turbo
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Whatever you do, don't swap the two RPM relays (that Mark/Amanda was talking about). They are DIFFERENT.
 

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Discussion Starter #7
Well noted, I did see the part in the chapter as to the description of each relay. I'll go over that when I get back from vacation and go through each one. I'm anxious to take the old girl out for a spin since our weather is so nice already. Thanks to everyone for the help so far.
 

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In total agreement with MRDAN on that one. I've never seen relays go bad unless they come into contact with water... however the 'no dash lights' is interesting.

On the back of the starter solenoid are two wire terminal connectors,
I think one feeds the ignition system. These connectors a prone to cause power problems and I would give them a check out.

The ignition and auxillary ignition are supplied power through two relays 'Temp Change Over Relays'. In order for these relays to work they both ground through a thermal switch. If it cannot ground through that switch or the switch is bad it affects the ignition and aux. ignition. I would check the ground connection for fungi or a broken wire. Both wires are yellow/black the one going to the 'Thermal Switch' has a double yellow/black wire coming from the relay connector. Follow the stray lead to the switch and it's ground.

According to the schematic these relays are the same looking at the contact points. The relay powered from the starter solenoid will have a yellow/purple wire. There should be one wire coming off to the second relay,
yellow/black These connect to relay #2 'Temp Change Over Relay'

As I said before the yellow/black should share another wire of the same connector going to the 'Thermal Switch' and the to ground. The Green wire is tapping off both relays to feed the ignition switch wire which will feed a ten AMP fuse.

The 'no spark' could be a bad pick up wire, the 'no dash lights' makes me think otherwise because a bad pick-up wire would not cause dash lights to go out.
 

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Discussion Starter #10
Thanks for the help guys. After a nice relaxing week in AZ playing golf, I got back to looking at the Lotus last night. After looking at the schematics again, I decided to pull the ignition power relay in the front compartment apart. Sure enough, it was not making contact even though it looked fine. Once I cleaned up the contacts a bit and put it back together, all my lights and fans were working properly and the car started up.

Now after all of that, it's only running mostly on two cylinders by looking at the plugs. I have good compression in all cylinders, but plugs 1 and 4 are wet while 2 and 3 are sooty. I guess I'll be ohming the wires tonight and pulling out the distributor cap to hunt this one down, Cars and Coffee is this Saturday. :)
 
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