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Before I accidently set it on fire . . . again.

Footnote - DeLorean DMC-12 is equipped with a Bosch electronic ignition system ...alternating voltage is produced... The pules is transmitted to the ECU module and its voltage will vary between 0.3 volts and 100 volts depending on engine speed....The ECU module controls the operation of the ignition coil and determines the proper dwell angle.

A scope or automotive multi-meter is required to measure that AC voltage.

DeLorean DMC-12: Model years: 1981–1983

Tom - Does your engine use a vacuum pot?

Again, grounds/positives must be cleaned...a good looking ground may be oxidized.

Specs are at that cite.
 
Footnote - A special coil was used...coil must be of OEM spec. Coils are designed around a specific dwell time interval. If dwell time on coil is within specs, and if existing ECU module is within specs, it might be possible to use a MSD setup...but they would have to be consulted.
 
The distributor has only one hose on the pot. The hose routing diagram on the hood is not correct. Finally found the correct at the back of the climate control greenbook halfway through this adventure. At the moment it seems to run correctly except for a high idle most likely due to my last efforts.

I have been meaning to summarize about a thousand posts on this saga for some time. This is as good a time as any.

I bought this car from an eighty-six year old gentleman in April 2012 in non-operational condition. It was his wife's car and had resided in his hay barn for 19 years after she died of cancer. I visited the hay barn. For the last year of its hibernation it was in the care of Elroy, an ASE certified Master Oil Change Technician.

He changed all the belts, hoses spark plug wires, distributor cap and rotor, pressure pump and lift pump and had his way with most of the rest of the car. The rotors, calipers and pads had all been changed. He opened the fuel distributor and left it leaking. I found evidence that he had been lots of places. Washers were missing in the intake manifold and two bolts securing the throttle body were too long and bottomed into their holes without sealing the gaskets. Oh, and I found a coolant hose clamp under the left valve cover. He said he changed both the lift and pressure fuel pumps but never got it running.

It would run on starter fluid at this point. The fuel tank was a rusty mess and destroyed the lift pump even before I could get the old gas out of the tank. I pumped it dry twice with the lift pump, or so I thought. Elroy had bent the steel tubes down to the pick-up filter at about a 30-degree angle so there was always a gallon or two of old rusty gas below the filter screen.

New tank, new lift pump, new pressure pump, fuel lines flushed 3 times. Oh, a new gas cap since the car came with a locked one without a key. Fuel distributor commercially rebuilt and then sent back for a second rebuild due to fuel imbalance. Injectors tested and found to be unsalvageable. New in-box Bosch injectors. Rebuilt control pressure regulator more than once. It would hold for a while then fail again. Replaced with a professionally rebuilt one.

The frequency valve would not reliably operate. Sometimes it would vibrate other times it would not. Replaced system relay and ultimately had to swap out the computer. The car came with a VW 4-cylinder computer but I found a correct 2.8L PRV one. Now all that works.

Fuel delivery was still unbalanced but rebuild company out of business so I did it myself with the steel gasket and O ring rebuild kit. That solved the fuel problem.

The spark advance was initially found to be five degrees after TDC and also found the distributor off by one tooth. Because of all the many strange issues found I pulled the entire front end off the engine to verify crank to cam to piston to distributor alignment. I suspect that Elroy had tried to time to the #6 cylinder rather than #1.

The spark at the plugs was questionable. Plugs fired but three different timing lights would not reliably flash for timing check and the engine ran poorly. Replaced ignition pick-up coil inside the distributor, the insulated lead from the distributor and swapped out the ignition module with another used one. Not to miss anything I replaced the coil with a NOS Bosch coil.

Let’s not forget the few days diagnosing and replacing the ignition switch. It was physically broken inside.

Exterior was painted, interior leather, which was everywhere, was cleaned, treated and painted with vinyl paint. Coverlay dash cap installed and after giving up on dying the carpet new was installed.

I'll come back and plug in some pictures to make this a one page summary of 8 years of hobby work. It's been fun and frustrating.
 
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I really believe that when I resolve the vacuum leak it will fine. The thousand things wrong with the car and extended period of time to resolve them were due to very long term storage, an unqualified person working on it for a year and me being the extended families auto service center. It was always a very sound rust free car with only 25k miles on it.

Never did get this forum involved into the details of restoring a brother's Jeep, twice, and a granddaughters Toyota wreak during the past 8 years.

Gave the wife's Miata to a granddaughter, giving the Jaguar Convertible to a grandson and the V8 Volvo wagon to my brother. Planning on keeping the Bertone for local lunch travel and some local car shows.
 
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At the moment it seems to run correctly except for

I never followed your saga, but this previously cite mentioned gives specific timing information required, if it applies to your setup. Some of my previous comments are irrelevant to this DeLorean DMC-12 ignition system, but I never had a firm understanding of your setup; as noted.

An oscilloscope should be used to evaluate, if pedal performance is not good; if you need a scope, shoot me a PM. With those specs for the DeLorean, a person can pinpoint an ignition issue.

PS: Fast Idle - Timing might be advanced too much...not good...recheck
 
It is at 8 degrees before TDC at the moment. Vacuum leak after pulling the entire intake system off recently to verify distributor setup most likely source of high idle.

Rainy, cool day. Time for a nap.
 
8 degrees before TDC at the moment.

???? Is your engine timing specs the same as this DeLorean DMC-12 ????

Basic ignition timing: 13+2 degrees BTDC at 775 +50 RPM (vacuum advance disconnected)

Spark advance -- vacuum (at idle speed): 5 in.hg. = 3 degrees; 10 in.hg. = 12 degrees; 15 in.hg. = 20 degrees [via hand held vacuum pump ]

Spark advance -- mechanical: 1000RPM (engine) = 0 degrees; 2000 RPM (engine) = 10 degrees; 3000 RPM (engine) = 14 degrees; 4000 RPM (engine) = 20 degrees

Trigger/stator pole air gap: 0.25mm

ETC: https://delorean.fandom.com/wiki/Ignition_system
===================

Footnote - A mechanic would have to have a good reason for changing a distributor's tooth position. I've pulled GM distributors for priming oil pump (hydraulic lifters), and only once in fifty plus years for a tooth change.
 
Long ago. All cylinders 165+.

I was very concerned of freeze damage to block, radiator, heater core but the only thing I found was the heater core split.

Yeah, good numbers there. It's got to be some spark advance or fuel air related for that thing to run but have no power. I think you are on the right path. Just frustrating with how much stuff was marginal or bad.
 
'Pulse generator' in this distributor... Hall Effect got used in more modern systems.

A Variable Reluctance Sensor might be the correct engineering speak. Short read at cite below.

Hall vs. Variable Reluctance Sensors

"In 1879 Edwin Hall devised a way to measure voltage based on electrons moving on a current carrying conductor in a magnetic field."
===================

Tom's Volvo can be Megasquirted, but I would use a Hall sensor setup since they work at zero engine speed plus .
.
 
A Variable Reluctance Sensor might be the correct engineering speak. Short read at cite below.

Hall vs. Variable Reluctance Sensors

"In 1879 Edwin Hall devised a way to measure voltage based on electrons moving on a current carrying conductor in a magnetic field."
===================

Tom's Volvo can be Megasquirted, but I would use a Hall sensor setup since they work at zero engine speed plus .
.

Or in Keep it simple stupid speak... The pulse generator makes an A/C current. Every time the current switches from negative to positive the switch is triggered. We test a pulse generator using the low voltage A/C setting on the Fluke meter.

Hall effect makes an on/off signal. Ones an zeros. More precise.
 
Or in Keep it simple stupid speak... The pulse generator makes an A/C current. Every time the current switches from negative to positive the switch is triggered. We test a pulse generator using the low voltage A/C setting on the Fluke meter.

Hall effect makes an on/off signal. Ones an zeros. More precise.

Not exactly. Hall effect sensors put out a variable voltage based on the strength of a magnetic field. It would have to be paired with a CT or other threshold sensor to output an on/off signal.

A variable reluctance sensor is similar in application but rather than detecting a magnetic field, it emits a magnetic field and detects ferrous objects. It also outputs a variable voltage which is related to the proximity of the transducer to the object it is detecting.
 
pulse generator

Both ignition systems are based upon a "pulse generator," and both designs represent an electronic circuit, where one is analog, and the other digital.

Wiki
1. Pulse generator
2. Electronic circuit

Both of these ignition systems used will control the "proper" dwell angle for a given coil, whereas, in a point based distributor, the dwell angle is determined by the point's gap.

Point System - Checking the dwell angle
 
A variable reluctance sensor....outputs a variable voltage which is related to the proximity of the transducer to the object it is detecting.

Ah yes, very important point: Air Gap

Trigger/stator pole air gap: 0.25mm

ECM is expecting a range of lower/higher voltages to operate...he who screws the air-gap pooch will not be within the engineered specification.

PS: Over at Megasquirt forum, one poster used the expression "VR signal."
 
A hall effect sensor is a switch and generates a square wave signal

A VR sensor generates a sine wave signal

A Hall effect sensor is powered, a VR sensor is discrete.
 
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