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> Makes me wanna cry -- D-Jet torment, 1973 1.7 D-Jet malfunctions...
Mike!!
post Feb 16 2026, 09:16 PM
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Aloha,
I'm just about ready to cry uncle, I've been trying to get my 1973 1.7 back on the road for literally years now. Every time I think nothing else could possibly be wrong, something else is wrong. The car enjoys tormenting me.

Long Story Short: here's my problem, after fixing just about everything that needed fixing, I can't get the thing to run reliably, fires right up, and if I pump the gas continuously I can get it run, but if I just hold down the gas or take my foot off the pedal it either dies or does this oddly impressive extreme low-idle / dieseling at about 50 rpm. The issues started when I replaced a blown out MPS with a shiny rebuilt one from AA.

Long Story Longer: The car had NO rust, it was parked in a garage in Oklahoma since 1981. The car's engine always seem to work fine since I bought it 4 years ago, fired right up, ran smooth, but I couldn't drive it since the brakes were fried, the shocks were trashed, fuel injectors were cracked and dripped gas, all electrical harnesses were literally duct tape together in places, all fuses were 30 amps because anything smaller would instantly pop, fuel pump was literally dangling from the fuel lines and power leads under the car (one way to prevent vapor lock I assume), door handles were non-functional, etc. etc.

So slowly over the course of the last four years I've replaced or repaired everything, rebuilt the electrical harnesses, re-located the fuel pump under the fuel tank ala the old service bulletin, stainless steel fuel lines, repaired or replaced everything that was broken.

I pulled the engine and transmission, cleaned out years of sludge. Replaced the thermometer bellows thingy, Replaced the dizzy with a 123Ignition, replaced the oil pump, changed out the clutch, etc. etc.

After all this I put the engine back in, and to my utter astonishment, it fired right up! Like immediately! I took it on a couple of test drives around the block and I knew something was not right, no power, misfiring, just not working. But at least now I thought I had a rolling project rather than a garage decoration. It was running enough to make a run down to the gas station and put a couple of gallons of gas in, but I barely made it home, it actually completely died just as I coasted to a stop in my driveway.

Did some initial troubleshooting and it turns out the MPS was blown out, it did not hold vacuum at all, I was essentially running as if WOT the whole time. I don't know why I didn't check that before. Plugs completely fouled, oil smelled like gas, etc.

I then bought a rebuilt MPS from AA and now, for the life of me, I can't get the engine to run.

Diagnostics:
Good / okay compression all cylinders (110 - 130PSI)
New MPS tests fine, or as fine as I can tell with a multimeter and vacuum guage
When it was running I was able to shoot/adjust the timing 27 @3500RPM, I cannot shoot the timing now because the engine does not run right
123 Ignition has basic custom curve 7.4@500rpm, 7.4@1500, 27@3200, flat line 27 to 8krpm with rev limit at 6krpm, MAP curve zero'd.
Fuel pressure was 29PSI, but I cranked it up a little to 32PSI, I figure 10% boost, but that didn't help
CHT seem to be on the curve, it's warm here in Hawaii
AAR functions properly
Adjusted valve clearance to spec when I had the engine out
Sent the injectors out to Mr. Injector, all are good now.
TPS seems to test out correctly with a multimeter.
Replaced fouled plugs, oil and oil filter

I ran though a bunch (all???) of the D-Jet troubleshooting posts here and The Paul Anders Rennlist site as well as D-Jet A-Z by Dr. DJet. No joy.

What am I missing here? Anyone have any insights? I actually find it really hard to believe that the rebuilt MPS is faulty, but maybe? Is there anyway that the timing is now off because I set the timing when the engine was running super, super rich? What else should I look at?

I'm committed, but sometimes I think this silly, little yellow car is going to get the best of me.

Thanks!

P.S. Really, thanks to all of you on this here forum, I could not have even gotten this far without this collected wisdom and experience, now I just need that last little clue to get my teener rolling again...



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914sgofast2
post Feb 17 2026, 12:07 AM
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Have you replaced the 4 hoses on the intake tubes to the intake plenum? After 50 years they are shot. Make sure you use the smaller diameter hoses for the 1.7 engine. Don’t try to use hoses for a 2.0 engine.
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