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Having problems with my 5.0 tbi having no power

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Old 06-03-2018, 08:52 AM
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Having problems with my 5.0 tbi having no power

I have a 91 5.0 tbi that seems to not want to spin the tires just makes a weird humming noise and no burning rubber. Tried adjusting the timing and then tried spinning the tires but nothing. A few months ago I had to change out the computer and distributor has a new map sensor and tps sensor bought new injectors,fuel pump,fuel filter and still nothing but then again she does have over 200,000 miles so maybe I need to replace the engine not sure what to do and help would be appreciated. And when she shifts into first its kinda hard and it sounds like it's misfiring a little not to bad. Any suggestions plz
Old 06-03-2018, 08:24 PM
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Re: Having problems with my 5.0 tbi having no power

Your 305 made 170 horsepower when new (IE: not much). Less 200k miles of wear, an automatic transmission(?), and 2.73 rear gears, I would not be at all surprising if it could not spin the tires in any substantial way.


FYI...timing spec is 0. Anything more that 4* or so is detrimental to performance.
Old 06-03-2018, 09:10 PM
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Re: Having problems with my 5.0 tbi having no power

Could it do it before and not now? You need one of two things, more power or less traction. Look at it this way, you won't lose a race because you blew off the tires. I kid, I kid, seriously now, that thing probably tired and didn't have much to start with. Its time to do the community proud and breathe new life into that engine.
Old 06-03-2018, 09:16 PM
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Re: Having problems with my 5.0 tbi having no power

My LO3 has problems with no power also.. That's why I'm getting this old boy ready
Old 06-03-2018, 09:35 PM
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Re: Having problems with my 5.0 tbi having no power

Not even a Corona will make the L03 faster.


Good beer though.
Old 06-04-2018, 05:51 PM
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Re: Having problems with my 5.0 tbi having no power

I'm just gonna rebuild the engine
Old 06-04-2018, 06:06 PM
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Re: Having problems with my 5.0 tbi having no power

Change the cam and throw away your exhaust system and replace with a 3in system with good headers and y-pipe and it will be a different animal. Or better yet toss the engine and find a LO5 or L31.
Old 06-05-2018, 10:54 AM
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Re: Having problems with my 5.0 tbi having no power

200k miles on a 305 TBI isn't that much. The low power keeps them alive for a long time. You mentioned that you changed the distributor and "messed with the timing". Are you sure you installed the distributor correctly? Where you adjusting the timing with the EST disconnected? If not, your timing is way off and the car is limping. Don't throw any more parts at the car, that just introduces more variables. To echo what was stated before, was this decline in power noticed as soon as you started messing with parts? Or has it been a slow decline? I would baseline everything. Fuel pressure, timing, etc etc.

Last edited by ShiftyCapone; 06-05-2018 at 10:59 AM.
Old 06-05-2018, 03:24 PM
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Re: Having problems with my 5.0 tbi having no power

mmmm, Corona

Never understood the fascination w/ burnouts, never had the spare money just laying around to go buy tires that would literally go up in smoke.

Burnouts don't necessarily indicate that your car is fast, just that you're overcoming the traction of your tires. I've had tires in such rough shape that a carbureted '70's smog-dog 4-banger could have lit 'em up.

While you're sitting there spinning your wheels (literally), the other guy is halfway down the track or to the next stoplight (or to the Kwik-E-Mart for another cold one).

Breaking loose is not good, traction es muy bueno.
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