89 with rough idle
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89 with rough idle
I’ve got a low mileage 1989 E-350 with a 351 engine. I could use some help trouble shooting a rough idle problem. Acceleration and overall driving is good. <?xml:namespace prefix = o ns = "urn:schemas-microsoft-com
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What kind of care has it had? Are all the vacuum hoses good? How about a general tune up? Plugs, cap, rotor, wires, pcv, egr cleaning, MAF cleaning(if it has one). If it has been sitting for a long time, I woud suggest running a few cans of BG44K fuel system cleaner through it.
More Turbo
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From: Sweden
upper-to-lower (plenum) intake manifold gasket- likely
vac leak. Check the vac lines where they pass over the passenger side exhaust manifold. Check the steel "coffee can" vac reservoir behind the starting battery for rust (very likely!)
slack in timing chain (you say low mileage so I would find it unlikely)
vac leak. Check the vac lines where they pass over the passenger side exhaust manifold. Check the steel "coffee can" vac reservoir behind the starting battery for rust (very likely!)
slack in timing chain (you say low mileage so I would find it unlikely)
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Joined: Oct 2001
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From: Idaho
tradesman -
Having struggled with my '89 E250 and fuel injected 460, I can tell you a few things. First off, you don't have MAF, you have speed density. So, don't try to clean the MAF...you don't have one.
On my van, I found that one of the plug wires was actually sparking through the boot and arcing to the exhaust manifold. Easy enough to see it, put the van in the shop where there is little light and start it with the dog house removed...you'll see arcing if the wires are bad. My wires were the factory originals and although they looked to be in very good shape, they weren't. A complete tune up is in order 1) because it can resolve the problem and 2) if it doesn't fix the problem, then you have a correct baseline from which to start looking at other problems.
I too had a rough idle, loss of power at full throttle, and a check engine light. I replaced the fuel filter, air filter, plugs, wires, cap, rotor, and PCV valve. The van runs vastly better now. Also, the EGR can be the problem as well.
Start with the tune up and see where that gets you. I think I spent a total of $100 including having someone else do the fuel filter and the rest myself.
Keep us posted...
Having struggled with my '89 E250 and fuel injected 460, I can tell you a few things. First off, you don't have MAF, you have speed density. So, don't try to clean the MAF...you don't have one.
On my van, I found that one of the plug wires was actually sparking through the boot and arcing to the exhaust manifold. Easy enough to see it, put the van in the shop where there is little light and start it with the dog house removed...you'll see arcing if the wires are bad. My wires were the factory originals and although they looked to be in very good shape, they weren't. A complete tune up is in order 1) because it can resolve the problem and 2) if it doesn't fix the problem, then you have a correct baseline from which to start looking at other problems.
I too had a rough idle, loss of power at full throttle, and a check engine light. I replaced the fuel filter, air filter, plugs, wires, cap, rotor, and PCV valve. The van runs vastly better now. Also, the EGR can be the problem as well.
Start with the tune up and see where that gets you. I think I spent a total of $100 including having someone else do the fuel filter and the rest myself.
Keep us posted...
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Originally Posted by Dannym
upper-to-lower (plenum) intake manifold gasket- likely
vac leak. Check the vac lines where they pass over the passenger side exhaust manifold. Check the steel "coffee can" vac reservoir behind the starting battery for rust (very likely!)
slack in timing chain (you say low mileage so I would find it unlikely)
vac leak. Check the vac lines where they pass over the passenger side exhaust manifold. Check the steel "coffee can" vac reservoir behind the starting battery for rust (very likely!)
slack in timing chain (you say low mileage so I would find it unlikely)
Good call on the vac canister. My 78 is leaky there and idles like crap until it is warmed up.
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