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Fri Apr 12, 2019 6:27 am

Good morning everyone! I have searched and read about 100 pages on here the last few days looking for my problem with no luck. The problem is that it will start fairly easy cold, have to hold the Throttle, for about 20-30 sec then it idles great revs great sounds great no missing. But if I try and drive it I can get about 1/2-3/4 of a block before it surges bucks and pops then dies. Will start right back up but can’t put it under load or even rev with out it piping will not idle without stalling. I have replaced fuel pump steady 30psi, new points and cond, Set timing, torqued heads, set valves, MPs holds vac. Replaced all fuel and vac hoses. Checked res on temp sensors. If I let it cool down most of the time it starts right up. Also pulled and clean trigger points

Fri Apr 12, 2019 7:17 am

I am still very new at this whole d-jet thing but I am wondering if this may be a aar issue? I thought I read the system wants 28psi too?

Fri Apr 12, 2019 7:56 am

I checked the aar, it fully closes even pulled the line and capped it to test. I have read 28psi also, but also read bump it up to 30. Had it at 28 and no change in the way it ran bumped it up to test a higher pressure.

Fri Apr 12, 2019 8:04 am

Still sounds like a vacuum leak to me. Injector seals, hoses hidden under the IAD, etc.

Fri Apr 12, 2019 9:26 am

Start with the basics. Go through tje ignition and make sure its PERFECT.

Then check every hose for cracks and loose fit. I clamp ALL of mine no matter how small. This includes boots on runners and that hose you cannot reach behind the plenum.

Then....yes....you already checked the AAR....but also vacuum test the MPS and deceleration valve if you have one.

Check your input voltage to the fuel pump relay and the EFI system relay.

And.....check your fuel pressure at idle. Needs to be 28-30....no higher.....but it needs to be stable.

Check all wiring plugs in the efi harness...especially the three ground wire bundles on the case centerline . Ray

Fri Apr 12, 2019 10:28 am

Plugged exhaust? Just a thought. This is exactly how they act when the stuffing in an OE muffler comes loose and tries to come out the tailpipe. Instead of distinct firm pulses out the TP it feels weak, or like a hair dryer on low.

Distributor not advancing could also cause it.

Fri Apr 12, 2019 11:29 am

Crud in the gas tank plugging up the fuel sock in there.

Fri Apr 12, 2019 11:34 am

Mike Fisher wrote: Crud in the gas tank plugging up the fuel sock in there.

Good thought! Might be the square filter, too.

Fri Apr 12, 2019 3:55 pm

Checked all the ignition its prefect, have replaced all the vac lines, and did a spray test with carb clear, MPs holds vacuum. It now runs great sitting still, revs sounds good idles great stead 29 psi fuel pressure. I had a trigger point sticking so I replaced them. But if I move it rev or 1st pops bucks and dies no power at all even at idle. I’ll check the exhaust. Did just notice that the ground strap from the trans was green so I grabbed it and it ripped in half

Fri Apr 12, 2019 3:58 pm

Also pulled the tank and cleaned it when I replaced the fuel pump. Just a note I got the car in an auction and have no history on it, was last tagged in 1986. The fuel pump was hanging when I got it so I tested and soaked it with no luck so I replaced it.

Fri Apr 12, 2019 4:48 pm

paulmont1719 wrote: Checked all the ignition its prefect, have replaced all the vac lines, and did a spray test with carb clear, MPs holds vacuum. It now runs great sitting still, revs sounds good idles great stead 29 psi fuel pressure. I had a trigger point sticking so I replaced them. But if I move it rev or 1st pops bucks and dies no power at all even at idle. I’ll check the exhaust. Did just notice that the ground strap from the trans was green so I grabbed it and it ripped in half

Also clean check and adjust the TvS.

Also.....if it has the MPS with the large aotted outer screw....about 1/2" in diameter....which iw not,a screw plug its an adjustment........if the tqmper proof epoxy has been removed......and if that plug is screwed qll the way in and touching the copper plate inside at idle.....or if that screw is missing altogether...........either or these will cause the exact symptom you are having. Ray

Sat Apr 13, 2019 12:15 pm

Found oil in the mps cleaning it now, TVs looks good and seems to be adjusted correctly