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  • November 28, 2024, 12:45:45 PM

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Author Topic: Engine only starts in bursts. Electrical issue vs. fuel issue?  (Read 5577 times)

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Offline Horse

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Engine only starts in bursts. Electrical issue vs. fuel issue?
« on: November 18, 2011, 01:18:13 PM »
I bought an 87 wagon in sedan.  She's stock and runs like a champ.... when she starts.  I was losing power in the middle of the road and have replaced the battery, alternator and starter in that order.  (should've done the starter first, the bell housing was cracked clean in half.) 

As of yesterday the new starter is cranking great and when we pour a little ether down the carb we get the engine for a quick burst and then it dies out again.  No matter how much we flutter the gas, it dies out as soon as it revs up. I think I've solved my electrical issues, all my wires and connections look fine.  As far as the vacuum stuff goes, this is the first Eagle I've seen in a while that has every hose and connection hooked up correctly... except the back pcv valve (pcv air in, I believe).  From the looks of it, the pcv has been flat out missing for a while.  In my experience though, a vacuum issue will cause the car to run ruff, or stall, but not prevent it from starting.

Now it has been sitting for a week while I was waiting on money for the starter and it didn't have a lot of gas in it to begin with.  Could it be as simple as throwing a gallon of new gas in and priming the carb? This was yesterday and in this part of Michigan the temp was around 33.  This car has always ran COLD and takes a good while for her to warm up.  It's a solid ten degrees warmer today and tomorrow, so maybe I'll have different results when I go back there.

Hope there's some ideas out there so I can post a bunch of pics and brag about how neat my "new" ride is.
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Offline shaggimo

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Re: Engine only starts in bursts. Electrical issue vs. fuel issue?
« Reply #1 on: November 18, 2011, 01:38:02 PM »
A large vacuum leak such as a pcv port not blocked, could cause this issue, did you block the port off? or leave it open?

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Offline Horse

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Re: Engine only starts in bursts. Electrical issue vs. fuel issue?
« Reply #2 on: November 18, 2011, 01:55:12 PM »
it was open.  By the time I found it, we were too cold to be outside working on cars.  The seal on the valve cover is wrecked making my old man think it'd been open for a while.  But I could've sworn everything was hooked up when I bought her.  I go out there today or tomorrow and I'll pick up a new valve (I have no idea where that valve went to) or at least plug the hole.
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Offline Horse

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Re: Engine only starts in bursts. Electrical issue vs. fuel issue?
« Reply #3 on: November 25, 2011, 01:59:36 PM »
Turns out she just needed a fresh gallon of gas.  The PCV valve however makes her run a lot better in 2nd gear, she was having trouble between 15 and 30.

But hey, are Eagles really that slow and steady on acceleration?  Does the efi really make that much of difference in horsepower? My last one had the efi or whatever it is, y'know bigger cap, bigger wires, hotter coil.  I might keep it stock but next tune up I could do the bigger electricals.
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Offline shaggimo

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Re: Engine only starts in bursts. Electrical issue vs. fuel issue?
« Reply #4 on: November 25, 2011, 03:27:07 PM »
I'm not a believer in stock efi making more power than a proper carb, over a bbd, sure, the bbd is no power maker, by any means (when you start talking a mega squirt custom tune, then ok, f/i will take the win over any carb, lol). I went from stock Fuel Injection on my 4.0, to a 4bbl carb, seat of the pants, I seemed to have lost no power, I gained in the top end noticably (both by me and a stock cherokee owner). Where my injected jeep would peter out at about 65 mph, the 4bbl equipped keeps on pulling strong (same engine, same gears, same tires, only difference being a carb, intake, and ignition system). The only real way to prove that would be on a dyno though, put the stock tire size back on, and pull against a stock efi 4.0. Go with a better carb and I bet you'll feel a difference.
88 xj cherokee- ((4)(4))2
81 malibu 4dr- Identity Crisis
81 SX4- gf's
84 Eagle 4dr sedan- it followed me home... ::)
http://www.cardomain.com/id/Oldsmoletic
CNY

Offline mudkicker715

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Re: Engine only starts in bursts. Electrical issue vs. fuel issue?
« Reply #5 on: November 25, 2011, 05:25:05 PM »
I second that.



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Offline Horse

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Re: Engine only starts in bursts. Electrical issue vs. fuel issue?
« Reply #6 on: November 25, 2011, 08:26:12 PM »
The Horse (my old 81) had the bigger wires, coil and all that from a ford 300 i6.  When I got the carb rebuilt and cleaned out by a guy who knew what he was doing the thing ran smoother than it had in years.  That well tuned carter never gave me problems after that (the tranny was a different story, thats what killed him).  I bought a motorcraft, intending to install it but never got the throttle linkage right and once my carter was tuned right I didn't care, had enough power for me.

But I think I have a different issue because I've noticed when it's not warmed up shes sluggish and sputtery in second and can't go up a hill to save her life, just stalled out trying to sputter up a hill this afternoon.  Once I get past 30 she runs better than just about any car I've ever driven and is a beast on the highway. 
Only you truly know your Eagle.

Offline Horse

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Re: Engine only starts in bursts. Electrical issue vs. fuel issue?
« Reply #7 on: November 25, 2011, 09:26:46 PM »
had to run up the hills just now, definitely runs rough when accelerating until I hit 30 then it smooths right out.  If i let her sit for too long I have to jam the pedal to the floor and give her several hard pumps for it to start.  I'm gonna try it in the morning and then post to fuel when I know more.
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Offline shaggimo

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Re: Engine only starts in bursts. Electrical issue vs. fuel issue?
« Reply #8 on: November 27, 2011, 10:01:40 PM »
It really sounds like you need to rebuild the carb. Any carbed vehicle is bound to be slightly angry on cold start and go's with no warm up time, all three of mine (well, two of mine, one of the gf's, lol), like at least a couple minutes of run time on those cold mornings, I wouldn't say as angry as yours sounds though.
88 xj cherokee- ((4)(4))2
81 malibu 4dr- Identity Crisis
81 SX4- gf's
84 Eagle 4dr sedan- it followed me home... ::)
http://www.cardomain.com/id/Oldsmoletic
CNY

Offline Horse

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Re: Engine only starts in bursts. Electrical issue vs. fuel issue?
« Reply #9 on: November 28, 2011, 05:02:50 PM »
Still having problemteady gas when warming up and will stall occasionally at low speeds.  She HATES being low on gas and wouldn't run when there was just a gallon in there, however that might be the gas gauge being punky when it gets low.  I haven't had a full tank in a while, ran much better then.  And of course it's time for an oil change.  I've been double footing it at stop lights when she's not warmed up.  Bought time to switch this topic to fuel.  My temporary fix is going to be change the oil and fill the tank until I have enough cash to swing by my carb guy.  Its still the original fuel pump, that could be an issue.
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Offline BenM

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Re: Engine only starts in bursts. Electrical issue vs. fuel issue?
« Reply #10 on: November 29, 2011, 11:53:22 AM »
I'm suspecting vacuum leaks and air being drawn into the fuel lines. So this is what I'd do:

Replace all the vacuum lines on it, and put some dialectic grease on the old rubber fittings at the ends where they attach to sensors. Dialectic grease is just Silicone grease and it doesn't swell the rubber, but it will help it seal and condition it. Wiping them down with spray silicone helps too, but be careful as silicone is hard to get off anything.

Replace all the rubber fuel lines, the bits around the tank especially, and the pieces around the pump, and from the return line to the filter.

Don't forget the lines to and from the canister. The canister vent to the vent line is the only one that can be safely ignored. Make sure the purge control line in the canister holds vacuum or it's just a leak. That's the one that goes from the temperature switches, and the control diaphragm can go bad. There should also be a restriction in the line that goes to the PCV tee right at the canister, if that's missing then there is too much air.

If that all doesn't fix it, temporarily plug the lines going to the EGR and canister. If one of those is leaking, that will make the difference, then you can troubleshoot by hooking up one line at a time.
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1987 AMC Eagle Sedan -- 1976 Pacer Coupe -- 1968 Pontiac Tempest Custom S -- 1940 Mercury (& a 2002 Jetta Turbodiesel, 5 spd., the Wife's Daily Driver)

 

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