'85 Starts, won't run

[85crownHPP]

Also, when I replaced the TPS, I'm not sure I put the spring that holds the choke connector thingie back on right. Can anyone find a picture that shows it clearly?

This thread has several up-close pics and a video of how that bit is supposed to work, along with a probably mostly correct explanation of how the choke/pulloff works.

http://www.grandmarq.net/vb/showthread.php?14587-the-unofficial-CFI-choke-thread

[gadget73]

"probably mostly correct". Now thats confidence!

[miamibob]

"probably mostly correct". Now thats confidence!

There's a Senate seat in Wash D.D. with his name on it!!

[85crownHPP]

Oh yes, gotta cover the brain farts somehow.

[Quackling]

Okay. Yes, Code 11 is all I got last time I checked.

I can't check timing, because I can't get it to stay running...

Found a couple breaks in vacuum lines, patched with tape temporarily until I can replace them. Line to the Map Sensor looks to be good.

EGR cleaned and functional. The passages leading to and from it cleaned out. The one was nearly choked off. Mostly open now.

Double checked the spring placement, and it looks right.

When I picked up the Fuel Pressure Test kit at Autozone, they looked up what I should find for this car. The computer said Key On Engine Off: N/A and Key On Engine Running: 4-5 lbs

I tested it Key On Engine Off anyway, and all it gave was a little bump of the needle as the pump shut off. Not what I expected, but it would explain why it said N/A.
Obviously I can't test it at idle, but I tested Key On Engine Running while feathering the gas and it fluctuated between 3-5 lbs. That seems about right based on what the computer said, but what do you think?

[Quackling]

Oh, the TPS. I don't have an analog meter (Thought I did, but no.) so I can't tell how smooth it is, but I can see the voltage goes up as the throttle opens.

[85crownHPP]

4-5 psi sounds odd, even for CFI. Are you sure they didn't look up the specs for a carburetor police car? That would explain the N/A.
Honestly I don't think I ever looked up the fuel specs when I had CFI, but damn!

To make sure I'm reading right, can you not even get it to maintain a high-er than idle rpm with your foot steady on the gas? It will only keep running if you actually are moving the pedal up and down to keep it going? That's definitely a strange one. Usually they just won't idle for crap without 'help'.
That makes me want to think about timing... worn out sloppy timing chain maybe, or the distributor got turned somehow. The only things that change with foot motion on the pedal are fuel volume, ignition timing, and vacuum.

[gadget73]

It should be more like 30-40 psi.

[kodiak]

Yep, 39 #‘s.



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[Quackling]

As far as the timing chain, the engine was rebuilt several years, but not that many miles ago. The timing chain and gears were replaced then. I'm sure of it, though I don't remember specifically...

And yes, you're describing it correctly. Only by moving the gas pedal can I get it to keep running. Holding the pedal still in any position and it'll die. I can get the RPMs up pretty good, a burst at a time, but never a constant speed. It doesn't make sense to me either... It ran fine when I parked it, a couple years ago. This problem appeared either while it sat or when trying to start. Maybe the fuel pump got clogged before I changed out the gas?

But if my fuel pressure readings are so far off, then it sounds like I'm looking at fuel pump issues. And, No, I'm not sure they didn't show me the carb police cruiser...

[Quackling]

What about the Fuel Pressure Regulator? Could that be an issue, and how would I go about testing it?

[Quackling]

Ah! Yes, they must have looked it up wrong. I just found it on the Autozone Web page. KOEO should be 35-45, and KOER should be 30-45.

[gadget73]

FPR is possible, but often when those fail it leaks. One test you can do is to disconnect the feed line from the CFI unit and dead-head it right into a pressure guage. If its not at least 50 psi, then the pump is bad or there is some massive leak between the pump and the gauge. Feed is on the passenger side. If that reads normal, but you see ~5 psi at the test port, its gotta be the regulator.

[Quackling]

It lives!!!!

With the pressure readings what they were, I wondered if maybe the fuel strainer was not letting enough fuel into the pump for it to work. So I decided to do some exploratory surgery today. Pulled the gas tank. I really didn't want to have to, but it wasn't as bad as I feared, thankfully. The rubber cylinder that goes around the pump itself (What it the point of that thing? Vibration damper?) was coming loose, and the strainer dropped off; had to go fishing in the tank for it. The strainer looked almost completely clean. But the four inch length of fuel line that connects the pump to the fuel outlet was seriously degraded, to the point of appearing to have holes. I pulled it off and pulled on it to see if it had any durability left:


Another victim,I suspect, of California's MTBE fiasco from a couple decades ago...

Now, I know its one of the Cardinal Rules at this point to replace that fuel pump, so I won't have to do all the work of pulling the tank out again. But I really don't want to spend the money on it unless I know it is the problem. So I decided to just replace that length of hose, put a new strainer on it, and put it back together.

And it runs!

Just to see, I put the Fuel Pressure Tester on it again. KOEO, it went up to about 38, then started dropping. KOER, held at about 42 pounds. I read that the pressure should hold with KOEO, but I'm not too worried about that.

Now on to making it pass smog...

[purplebomb302]

That hose looks horrible! I'd get the system cleaned. It's possible that there might be bits of rubber or some sort of rubber deposits in the fuel system someplace.

How far did it drop with KOEO and how long did it take to drop? may be looking at a fuel pump or injectors.