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> 74 2.0 LE Trouble- Backfiring & no power, New used MPS helped! Still some fine tuning needed
JRust
post Jul 28 2011, 01:41 PM
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Okay so I flat towed the LE down to Monterey CA 2 weeks ago. Car ran great while there. When I got home it was backfiring & running like crap. It has no power & won't stay running. The only strange thing was when I hooked it back up to bring it home. I got it all hooked up & forgot it was in gear (reverse). I put my Excursion in drive & had resistence. I didn't move more than 5 ft before I stopped. I went back & took it out of gear. I also had the ebrake on which I put down too. Started the car real quick & no problems. Turned it off & headed home. When I got unhooked at home it ran like crap (IMG:style_emoticons/default/WTF.gif)

So far I just checked all my hoses to be sure everything was on. I checked all my spark plug wires & they were as should be. I popped my distributor cap & saw nothing obviously wrong. Car doesn't want to stay running so I haven't pulled any spark plugs wires to see if it makes a difference. Just looking for some suggestions of things to check. It does have gas (IMG:style_emoticons/default/blink.gif)
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KELTY360
post Jul 28 2011, 01:47 PM
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My knee jerk response was your timing is off. But I'm not very smart and really bad at diagnosis.....so you can probably eliminate timing as the problem. (IMG:style_emoticons/default/blink.gif) Good luck Jamie, you've got almost a month to sort it out before you need to bring it to the BBQ.
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Rand
post Jul 28 2011, 03:25 PM
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The little braided ground strap between the distributor advance plates can cause this if it's breaking loose.
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JRust
post Jul 28 2011, 03:31 PM
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QUOTE(Rand @ Jul 28 2011, 02:25 PM) *

The little braided ground strap between the distributor advance plates can cause this if it's breaking loose.

I'll check that. Couldn't see how I would have screwed it up by pulling it in reverse that tiny bit. Figured it is something that just came loose on the trip. I just haven't found anything yet. Haven't had much time to look at it either (IMG:style_emoticons/default/dry.gif) . I'll get time saturday (IMG:style_emoticons/default/smile.gif) . Was just hoping all of you in your infinate 914 wisdom. Would give me some things to check (IMG:style_emoticons/default/rolleyes.gif)
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McMark
post Jul 28 2011, 04:41 PM
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Check to be sure the distributor is seated completely against the engine case. Or pull the cap and see if the rotor will spin or if it's still engaged to the drive gear. Also make sure the spring loaded center pin in the cap is still there.
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JRust
post Jul 28 2011, 08:53 PM
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QUOTE(McMark @ Jul 28 2011, 03:41 PM) *

Check to be sure the distributor is seated completely against the engine case. Or pull the cap and see if the rotor will spin or if it's still engaged to the drive gear. Also make sure the spring loaded center pin in the cap is still there.

All good there. I even swapped the cap & rotor with my backup. No change at all. I loosened the distributor bolt & advanced it a little. Still ran bad but acted like it when advanced. Retarded it a bit & it ran worse. Rechecked all my hoses & FI connections & all look good (IMG:style_emoticons/default/confused24.gif)
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hot_shoe914
post Jul 28 2011, 09:03 PM
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It is a cursed piece of (IMG:style_emoticons/default/stromberg.gif) and should be banished to a life in hell with a lousy 914 owner who doesn't take good care of his cars. Send that turd down here to me and I will punish it but good!
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ConeDodger
post Jul 28 2011, 09:11 PM
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You know what's coming Jamie...













Tow it down to Mark and he'll have it running in no time (IMG:style_emoticons/default/biggrin.gif)
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JRust
post Jul 28 2011, 09:18 PM
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QUOTE(ConeDodger @ Jul 28 2011, 08:11 PM) *

You know what's coming Jamie...
Tow it down to Mark and he'll have it running in no time (IMG:style_emoticons/default/biggrin.gif)

Yeah thats only $400 in gas & a full weekend driving. At least it is running. I should be able to figure it out eventually. Really seems like the timing all of a sudden is way off. Just not sure how that happened. (IMG:style_emoticons/default/dry.gif)
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Michael N
post Jul 28 2011, 09:54 PM
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Holy Crap! Not again. (IMG:style_emoticons/default/blink.gif)
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Mike Bellis
post Jul 28 2011, 09:59 PM
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Over lean fuel condition can make it pop and backfire. Check your filter and fuel flow.
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JRust
post Jul 28 2011, 10:13 PM
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QUOTE(kg6dxn @ Jul 28 2011, 08:59 PM) *

Over lean fuel condition can make it pop and backfire. Check your filter and fuel flow.

Good idea! I've got a spare filter. Easy enough to throw on to rule it out (IMG:style_emoticons/default/evilgrin.gif)
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Mike Bellis
post Jul 28 2011, 10:14 PM
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Check your injector output too!
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DRPHIL914
post Jul 29 2011, 07:39 AM
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QUOTE(JRust @ Jul 28 2011, 03:41 PM) *

Okay so I flat towed the LE down to Monterey CA 2 weeks ago. Car ran great while there. When I got home it was backfiring & running like crap. It has no power & won't stay running. The only strange thing was when I hooked it back up to bring it home. I got it all hooked up & forgot it was in gear (reverse). I put my Excursion in drive & had resistence. I didn't move more than 5 ft before I stopped. I went back & took it out of gear. I also had the ebrake on which I put down too. Started the car real quick & no problems. Turned it off & headed home. When I got unhooked at home it ran like crap (IMG:style_emoticons/default/WTF.gif)

So far I just checked all my hoses to be sure everything was on. I checked all my spark plug wires & they were as should be. I popped my distributor cap & saw nothing obviously wrong. Car doesn't want to stay running so I haven't pulled any spark plugs wires to see if it makes a difference. Just looking for some suggestions of things to check. It does have gas (IMG:style_emoticons/default/blink.gif)



Trigger point grounds checked?

I had the same thing happen driving home one day. One set of points grounds came loose, unfortunately it took a few days and switching everything else before I checked the grounds. (IMG:style_emoticons/default/blink.gif)
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Mr.242
post Jul 29 2011, 07:54 AM
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My guess: Pulling it in reverse and forcing it to turn forward. Maybe you jumped the distributor timing by a gear notch. Especially if you can adjust the distributor and it changes the way it runs.

That's my UN-educated guess.
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Dave_Darling
post Jul 29 2011, 05:13 PM
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I am told that running your engine backwards (specifically, this was in reference to spinning at an autoX and not getting the clutch in) can rupture the diaphragm in your MPS.

Worth a check.

--DD
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Tom
post Jul 29 2011, 07:06 PM
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Jamie,
I am in the same camp with the fuel filter. Might also check the injectors if there is anything in the fuel system breaking loose.
Tom
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JRust
post Jul 29 2011, 09:43 PM
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I don't have a spare MPS so I can't swap a new one in. I can give it the blow approach to see if it has pressure. I have some spare injectors off a 75 I can try. Easy enough to swap & wont screw anything up. I'll check the trigger points after the fuel part swaps.

I want to spend some time on my v8 though. I've got to rewire my relays. Then I just need to reinstall my interior. I've been a little stumped on how I want to do my firewall cap though. I'll rig a temporary one tommorow so I can get my interior done. I really want to drive it as it has been longer than the LE now (IMG:style_emoticons/default/dry.gif)
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Prospectfarms
post Jul 30 2011, 08:31 AM
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QUOTE(JRust @ Jul 29 2011, 11:43 PM) *

I don't have a spare MPS so I can't swap a new one in. I can give it the blow approach to see if it has pressure. I have some spare injectors off a 75 I can try. Easy enough to swap & wont screw anything up. I'll check the trigger points after the fuel part swaps.

I want to spend some time on my v8 though. I've got to rewire my relays. Then I just need to reinstall my interior. I've been a little stumped on how I want to do my firewall cap though. I'll rig a temporary one tommorow so I can get my interior done. I really want to drive it as it has been longer than the LE now (IMG:style_emoticons/default/dry.gif)



Sometimes good to take a break.

I've spent a great deal of time in Monterey, even purchased my bus there. I wonder how many members of this forum live on the MRY peninsula? I assume you were at Laguna Secca? Incredible venue.

I don't know much about type IV, but from reading about a hundred "engine trouble diagnosis" threads, your symptoms closely match distributor misalignment or bad ground. Seem to be lots of turned-around dizzy's out there. But if you are certain that after the aborted tow start, you: "Started the car real quick & no problems. Turned it off & headed home. When I got unhooked at home it ran like crap," then, as others have already said, your symptoms align with a fuel system clog or a loose ground in ignition system.

I do know that you can pull a couple of ticks of vacuum with your mouth. If you then cover the tube with your tongue and wait, it's easy to tell whether your MPS is holding Vac. Sounds kinda unsanitary but hey, I'm from Kentucky....

That's all I can add. Good luck with your cars. V8 sounds like a big project.
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computers4kids
post Jul 30 2011, 10:41 AM
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QUOTE(Dave_Darling @ Jul 29 2011, 04:13 PM) *

I am told that running your engine backwards (specifically, this was in reference to spinning at an autoX and not getting the clutch in) can rupture the diaphragm in your MPS.

Worth a check.

--DD

(IMG:style_emoticons/default/agree.gif)
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