2.9 ran like trash and has no spark now

[VirtualToaster]

I've been battling with this hunk of metal for the past two months (when i got it). It ran great and beautifully, before i touched the green/yellow coil wire that runs to the tfi and tach. After touching it, tach died and wouldn't move. Replaced ENTIRE ignition system (wires, pickup, tfi, you name it). Ran a new wire to TFI, motor started. Timing was off, but it ran and bucked.

Fast forward to two days ago (Wednesday), and the coil was acting up. Got a new connector (bat+ to coil was coming out) and ran better. Touched distributor, unplugged spout, set to ~500 rpm. Plugged in spout, idled at 1000 but would keep dropping, and coming back up, like something was wrong. Go to drive, and while it wouldn't buck at WOT, it also wouldn't go very fast. Almost as if the timing was retarded, or the spark was weak. Car dies, i touch some wires near the coil, it starts and I'm on my way. Then, at a stoplight, coil loses power entirely. Can't restart, no matter what i touch or do, it will not run. I ran battery power directly to the coil's power connector (forgot about my multimeter till later) and the interior lights came on. I'm not sure that's supposed to happen, but i'll keep going.

Now I don't know what the hell is going on. Tfi works (tach moves when key is first turned to START, up to about 300, then drops to 0), coil sends no spark (unhooked main wire and held a screwdriver to the post), and this is my third computer. (1st is original, probably still good, 2nd was out of an early 86, runs very rich and improperly BUT ran it great at WOT, 3rd is out of a late 86, current computer).

Frankly I have no clue what to do now. I'm going back to it tomorrow to pull codes. I know previously before i touched the timing, i got 33, 42, and 12. EGR not opening, O2 rich, and high idle. I think timing was at maybe 4-5 btdc. I lined up the crank pulley and the rotor at #1 while motor was near/at tdc (whatever the balancer mark suggests), and it ran but bucked like a bad TFI. It stopped bucking earlier (when less than 1/2 throttle) but would still buck after that.

Man. I hate early fuel injection. Can't wait until I piece my 302/351 swap together.

 

[VirtualToaster]

Checked codes earlier, and I have THESE as KOEO: 67, 84. THESE as continuous: 18, 22 63, 33.

I had AC, PO removed it and cut lines, I don't intend on replacing it. I unplugged MAP and TPS when trying to find the source of problems and found nothing. I do have a tach, but it really is not wired in the right way. (original wire from coil - to tfi with tach spliced in the middle is now coil- to tach, with separate wire for tfi.) Tach does work. Still at a loss here.

 

[gaz]

VT,

I could only ever get a aftermarket coil to work correctly off the negative side of the coil, never between the TFI and the coil.

 

[Paulos]

The '86 ECM is not compatible with the '87 wiring. You'll have EGR system issues, which is probably why you have a code 33. The '86 uses pin 52 for the EVR, and the '87 uses pin 33. There are other pins used and not used between the two years as well.

 

[VirtualToaster]

It worked just fine and sets the same code on the 87 puter anyway (have it in now), not like I care anyway.

Turns out the brand new TFI just kinda blew itself up. Switched it with the old one and it runs, but sounds like it's knocking. I know the motor is just fine, but it sounds like it's knocking. Strange. I'll go return this TFI for a new one if I have the receipt, otherwise I'll buy a new one at a different store.

 

[VirtualToaster]

A brand new tfi fixed it, sorta. Ran another KOEO, no codes. 41 stored in memory, o2 lean always.

Weird, cause it has no power and runs extremely rich, I think. Won't really rev, but will pop and bang when trying to floor it. Continues even when warm.

I haven't found a solution to this one, but maybe I'll find something. Someone said it would be the computer temp sensor, but I replaced that very recently.

VT out.

 

[Paulos]

Sounds like maybe a bad injector. Have you done a leak-down test to see if the fuel pressure holds?

 

[VirtualToaster]

I was going to do that tomorrow. My buddy has a fuel pressure gauge, and I don't. I don't know if the regulator is still good or not, but probably more likely that than an injector.

 

[VirtualToaster]

So, I just got back from testing my rail, and whatever. You may like this, I think I don't from what ford's pressures should be.

30 PSI @ 2sec runtime (key turn), pressure drops very slowly (uh oh!) it took 25 minutes for it to drop half a psi.
When running, pressure at 32-33 PSI, pressure goes up when throttle applied, for a split second, then drops right back down to 32-33, cold motor.
Unhooked regulator vacuum line, put finger over hole, engine still runs rich but revved higher, faster. Also a problem, but not main one?

I'm pretty sure this means my regulator is on its way out, but my booster pump is bad. Injectors too, most likely.

Sitting for 15 years really does ruin your fuel delivery system, doesn't it?