Tune up question

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Jan 6, 2002 | 03:24 PM

duck

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Joined: Apr 2000

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From: Pearland

Tune up question

I have a 1993 Bronco, w/351. The engine has 79,000 miles. I noticed that my gas mileage has dropped to about 9 mpg. It also has to turn over more and more, in order to start. Im hoping all this is leading to a basic tune up, of fuel filter, plugs, wires, caps and rotor.

Does anyone have a preference on plugs or wires, or any other things I might as well do?

Also, I noticed the fuel filter is relatively easy to get to, are there any tricks to not messing it up?

Thanks
J.M.

Jan 6, 2002 | 05:55 PM

honney

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Tune up question

My feeling on plugs is to just buy some basic Autolites, but it's up to you. Some report butt dyno gains w/the Bosch +4's but I've never tried them simply because of the price, plus you can't gap them yourself. As for the fuel filter, I think your '93 will require a special tool which disenages a bunch of "ears or tabs" to allow you to easily slide the fuel lines off. W/out the tool you'll destroy something and lose your sanity, w/the tool you'll be all smiles, but do wear goggles as gas in the eye is not good. Be sure to relieve fuel system pressure before starting, too. The tools you need are simply small round plastic rings avail at any parts house, shouldn't be more than $10. My '90 does not require the tool as it has plastic clips which are easily coaxed out w/a flathead screwdriver, but the newer trucks changed.

Jan 6, 2002 | 07:07 PM

JBronco

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From: Loveland, CO.

Tune up question

Be sure to check your ignition timing as well. You will need a timing light. Ignition timing being off is a major factor in increased start time. Also, I agree about the expensive plugs. I tried SplitFire plugs once, at 6 bucks a plug, and noticed no difference whatsoever.

Jan 6, 2002 | 08:17 PM

Rodeojoe

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Tune up question

J.M.

I have recently done a tune up on my 96 Bronco 351w. Started out with the check engine light, which indicated O2 sensor. Replaced all three. I then changed plugs (recommended Platinum plugs), wires rotor and cap. Bronco still has a low idle. I had the computer reset and the check engine light came back on. This time it was the EGR valve. Replaced that and I still have the low idle. Keep us updated if the tune up does the trick on the milage and the low idle.

RodeoJoe

Jan 7, 2002 | 09:51 AM

adelyser

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Tune up question

I have a '94 EB with the 351W, and just changed the plugs, wires, cap, rotor, and fuel filter this summer. I prefer to use the autolite platinum plugs, MSD Superconductor wires, Accel cap & rotor. I think the most labor intensive part was the fuel filter. Even with the correct tools, that front connector was really difficult to get off. I just kept on inserting the tool, and messing with the connector until it finally broke loose. If the connectors come off easily, it's about a 15 minute job.

Aaron D.
'94 EB Bronco 4x4, 351W, E4OD
'97 Expedition XLT 4x4, 5.4L

Jan 13, 2002 | 06:22 PM

duck

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Joined: Apr 2000

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From: Pearland

Tune up question

Ok gentleman,

Today I did the following:
New plugs and plug wires, new fuel filter, new breather element, new pcv, new rotor and cap. I can tell you that the plugs and plug wires appeared to bee the original equipment. And the rotor and cap were pretty much gone. Im hoping that it atleast raises my gas mileage, and I think it instantly ran better.

The fuel filter would have been impossible to remove, without the $10.00 part....(what a rip)....

I got so frustrated with the passenger side, back 3 plugs, that I had to call my best friend from work to come help. They are buried and awkward.

Thanks for all those that replied, and gave suggestions. I appreciate the help.

Jan 13, 2002 | 06:40 PM

JBronco

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From: Loveland, CO.

Tune up question

Again, be sure to check your timing. This is just as important as any other part of your tune-up. On a high mileage engine, it is acceptable, and even desirable, to advance the timing somewhat to make up for timing chain slop. You can advance it as far as you like, as long as it does not cause detonation. You will be able to advance it farther if you use premium gas, or if you don't drive in hot weather.