Fuel pump or ...?

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vcp
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Joined: Thu Jun 26, 2014 4:49 pm
My tercel:: 1987 Tercel 4WD wagon

Fuel pump or ...?

Post by vcp »

Replaced the fuel pump in my '87 TT4 a couple weeks ago and have had problems starting it a few times since. (Only intermittent.) When it happens, it turns over fine and seems like it's getting a trickle of fuel (so not just dry cranking), but throttle pedal has no effect and motor won't start. Has only happened a few times and so far, has eventually started if I keep trying, but ...

I assume I got a faulty fuel pump (new, Spectrum) but wondering about other possibilities to consider - bad fuel? air in line? Insights welcome. Thanks!
larry mcgrath
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My tercel:: 83 tercel v20 B/T (The ROCKET)98 toyota t100
Location: Wilds of Montana

Re: Fuel pump or ...?

Post by larry mcgrath »

Did you replace the fuel filter? located under the brake master cylinder, get a fuel press tester --auto zone- check pump press coming out of your new pump--- the line that goes to the carb Larry
vcp
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My tercel:: 1987 Tercel 4WD wagon

Re: Fuel pump or ...?

Post by vcp »

Thanks, Larry. Have replaced the filter a couple times in the last year while searching for solutions to other problems, so it's very new. But we didn't replace it when we changed the fuel pump. So maybe something got into it while we were changing the pump. Would be a nice simple solution ;-) Thanks for the idea!
rabalc
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My tercel:: 1985 SR5 4WD

Re: Fuel pump or ...?

Post by rabalc »

I have had fuel lines rust enough as to they don't leak, but suck air??
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Petros
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My tercel:: '84 Tercel4wd w/extensive mods
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Re: Fuel pump or ...?

Post by Petros »

is your float level correct? if you have the stock carb, it has a view window on the front side where you can see the fuel level in the float bowl (usually it needs to be cleaned off). If the float level is normal it likely is not a fuel starvation problem.

to make sure you can do a fuel pressure test with a gauge you can rent for free from Autozone (no reason to buy one because you seldom need to test fuel pressure). That was what larry was suggesting. A leaky fuel line, either rubber flex line or a rusty metal one, up stream of the fuel pump could suck air and give you low fuel delivery.

Also, verify that you actually have fuel starvation, could be weak spark. In the wintertime old wires and spark plugs sometimes have trouble getting going in damp weather. Once they warm up the marginal contacts get heated up and drives the moisture out and it runs normal after that.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
vcp
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Joined: Thu Jun 26, 2014 4:49 pm
My tercel:: 1987 Tercel 4WD wagon

Re: Fuel pump or ...?

Post by vcp »

Thanks, guys. Sorry for the delay responding - been tied up. And the issue has abated somewhat. Has been starting fine again for the last couple weeks as long as I don't touch the gas pedal at all (except for initial start of the day.) I used to have to give it a couple light taps, so had to adjust the habit after putting in the new fuel pump.

Have a new filter ready but not getting any other signs of clogged filter so gonna wait on replacing it. And if the problem returns will take a close look at the fuel lines, pressure and float level.

Thanks for the tips!
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