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Bad fuel pump...?

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Josh96

Probationary Member
26
0
May 24, 2015
Cedar City, Utah
I drive a 95 Eclipse RS 420a N/T Manual

For a few months I've been having an issue where it will not idle intermittently unless I keep my foot on the throttle. It will also do it where it won't quite stall but it will get really low RPMs and shutter and then kinda kick back up and do that for a while.

2 Weeks ago it wouldn't start for me after having this issue so I had it towed. Shop re-did wiring to fuel pump and replaced the connector and also put in a new relay. Seemed to be working fine. (Shitty shop IMO....)

Now it's been doing the same thing again. The only similarity I've seen is it seems to happen when my tank reads below or around 1/4 full. To test this out tonight it was happening again so I topped it off with 9.5 gallons and drove it home. By the time I got back (around a mile) it seemed to be doing better. I'm going to go for a quick test drive again in a little bit.

I also have new spark plugs within 5k miles.

At this point I am thinking fuel pump since I always hear it trying to start, it just never catches. It is also rough to start cold, I usually have to hit the throttle or it kinda shutters before getting up to a normal idle.

Any other thoughts for I drop cash on a pump.....?
 
Even though your air inlet isn't as long as a turbo you could have a loose fitting sucking in air that hasn't been metered. Since it hasn't been accounted for the engine is getting more air than it thinks.

So the ecu will squirt enough fuel to make the correct afr..

Since there's too much air the condition would be lean.

But the car will run like crap with air leaks. It can't hurt to double and triple check your connections.
 
Well luckily at about (according to gauge) 1/2 a tank remaining the issue has returned. Once again filling her up to full with 7.7 gallons has resolved the issue. Gee what would I do now that school is started besides dick around with my car >_<

At this point I suppose I should be replacing the fuel pump?

My only other possibility is I can see that the fuel pump re-wire has been done as I have that inline fuse coming off my battery and snaking back to the pump. The only thing I may try is re-doing either that whole shit or at least the O connector on the end that is on the battery since that looks to be quite corroded. Probably will review all the connections related to that re-wire I can...

Any other suggestions aside from checking for vac leaks before I drop $$$$$$$$$$$$$$$$$$$ on a pump?
 
Well luckily at about (according to gauge) 1/2 a tank remaining the issue has returned. Once again filling her up to full with 7.7 gallons has resolved the issue.
You might want to check the fuel pickup tube below the fuel pump (in the tank). It may be partially broken where it moves around (like to the surface) and so can't pickup the fuel properly. I've seen this on a car once.
 
You might want to check the fuel pickup tube below the fuel pump (in the tank). It may be partially broken where it moves around (like to the surface) and so can't pickup the fuel properly. I've seen this on a car once.

I'll check on that - probably tomorrow, thanks
 
Well I changed the connector on the pump re-wire for a fresh one and we'll see. Old one was pretty ugly.
 

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OK I lied. The fuel pump re-wire, upon further investigation, had not been done. That dumbass wire went to somewhere behind the stereo.

Anyway I did the fuel pump re-wire today. It is still driving afterwards so we shall see where this goes LOL.

I followed http://www.raktron.com/fuel/rewire1.html for the guide.
 
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