94 Corsica hard start stalls at lower RPM

[AcuraTech]

94 Corsica, 3.1 engine. Car starts pretty hard, but will start eventually. If you hold the gas pedal down a bit, it will stay running, and seems to run OK (no misfire). Once you let off the gas pedal it will kind of stutter and then stall out, almost like it's running out of gas.

I still have to do some diag on it, and go through all the basics (fuel, spark, etc), just haven't had time yet. Wanted to see if there was anything common with these cars that goes bad before I start digging into things.

This is a friend of mine's car who I'm trying to help out. Not real enthused, since its an old rusty, crooked, high mileage beater with poor maintenance. Would like to tell her to get something a bit more reliable, but she doesn't have much money so we have to do what we have to do!

 

[AcuraTech]

Was thinking maybe semi-plugged fuel filter, easy and cheap to replace, was going to start with that.

 

[-Clayton-]

If you can start by checking fault codes. I believe That car has OBD 1.5 though, So that may be out of the question. If the SES light is on then your more than likely looking at a bad sensor. You could always unplug sensors one by one until it starts running halfway decent, the ECM will use the default values for that particular sensor. Just make sure not to unplug them while it's running.

 

[VK56VD]

Idle Speed valve if this car has one? Run some fuel injector cleaner through it once the problem is resolved.

 

[mechtech2]

Clean your throttle body bore and plate real well.
Fix any vacuum leaks [esp the PV system], and intake leaks.
Then clean the idle air valve .
Are there any codes thrown?

 

[wavinwayne]

Crazy as it sounds, there should be a way to pull codes using a paper clip, if it has OBDI. I've done it on a Chevy Blazer with OBDI. Instructions can be found with a little googling.

Prior to buying my current vehicle, I drove a high-mileage piece of junk '94 Beretta for several years, with the same 3.1L engine. Although I never experienced the exact same problem you're describing, I did have a knock sensor go bad. You might want to check that. Also make sure the intake air hose doesn't have a crack in it (check the bottom).

Other than that, others have already made good suggestions. Good luck.

 

[eljefino]

agree with the idle speed control valve thing, had a 93 corsica with same issue. Hold on to the little screws that hold it in, if they drop deep in the motor you're a goner. Idle passages were full of oily goo, felt real good to clean it out.

Also possible your throttle position sensor is going flaky, when they go, the car does not know it's supposed to try to idle, (It only fights for a proper idle at an indicated 0% throttle) AND it rarely throws a code.

 

[AcuraTech]

Problem SOLVED. Car was (almost) out of gas. Obviously the sending unit or fuel gauge is off, because it registered about 1/8 tank. Had her get some gas and pour it in. And it started and ran fine.

Sometimes you just have to keep it simple. Basics first.

 

[kingrob]

Originally Posted By: AcuraTech
Problem SOLVED. Car was (almost) out of gas. Obviously the sending unit or fuel gauge is off, because it registered about 1/8 tank. Had her get some gas and pour it in. And it started and ran fine.

Sometimes you just have to keep it simple. Basics first.


Isn't it great when you rack your brain and panic over your vehicle only to find it's something so simple?

 

[wavinwayne]

Originally Posted By: AcuraTech
Problem SOLVED. Car was (almost) out of gas. Obviously the sending unit or fuel gauge is off, because it registered about 1/8 tank. Had her get some gas and pour it in. And it started and ran fine.

Sometimes you just have to keep it simple. Basics first.


WOW!!! My car problems are never that simple to fix.

 

[mechtech2]

Your vehicle education has been increased for any future situations like this .

 

[kelpie]

Yep, most cars do run better with gas in them.

 

[MarginCalled]

Originally Posted By: AcuraTech
Problem SOLVED. Car was (almost) out of gas. Obviously the sending unit or fuel gauge is off, because it registered about 1/8 tank. Had her get some gas and pour it in. And it started and ran fine.

Sometimes you just have to keep it simple. Basics first.
Technician of the year. ASE certified.

 

[AcuraTech]

I'm pretty happy about it because that was the first thing I had her do. Didn't replace ANY parts whatsoever. Also only spent about 5 minutes looking at it, so no time wasted. Good deal, because the owner of the car is broke as a joke, and can't afford to throw parts at it.

Next up is the oil leak in her car. When I looked at the car for the hard start issue it was 2.5 qts low! Ouch.

Like my dad, an appliance repairman. First thing he asks when people call about broken appliances is "Is it plugged in/turned on?" Many times it isn't.

Guy had his Subaru towed into our shop a couple weeks ago. Said it started then stalled right away. He had it in a few weeks prior for a broken fuel gauge, but didn't get it fixed. Guess what the problem was!

 

[onion]

I have an '94 Corsica, and have worked on quite a few of these 3100 engines. So I'll give you a bit of advice on the oil leak. A VERY common leak on these engines is the oil pump drive o-ring... and it's quite difficult to diagnose if you're not too familiar with the engine. If you look in the middle of the engine block, roughly under the throttle body, you'll see a round thingy about the size of a half dollar, held down by what looks like a distributor clamp. This is the oil pump drive- it's basically the bottom half of a distributor- has a gear and shaft to run the oil pump. When these leak (which is pretty often), the leak is under pressure, so it can make a real mess. The oil will run down each side of the engine, and lots of people mistakenly diagnose this as a leaky oil pan gasket or intake gasket.

If it turns out that this is the problem, then it's a fairly easy fix if you're comfortable working on engines. GM makes a new-style o-ring for this application... lasts longer/leaks less. It's brown. You'll also need a throttle body gasket and/or upper intake gaskets.

 

[benjamming]

Onion,

Does this o-ring leak result in quite a bit of oil loss? Does anyone make an o-ring for this that doesn't leak at all, not just less?

 

[AcuraTech]

Changed the oil on this car today, took a quick look at the oil leak. Nothing serious, just the usual old car leaks. Told her to just make sure to keep the oil topped off. Yeah, after 3k on an oil leaking/burning POS, the level is gonna be low by quite a bit.

Tried changing the fuel filter, psssht, yeah right! The hard line/nut is so rusted that something is gonna break if I turn too hard. Not to mention the nut is so rusted that the proper size wrench doesn't fit anymore. Lifetime fuel filter at this point, hopefully it's not plugged up too bad!

Car only has about 130k, and all I can say is WOW! That thing has fallen apart really badly, to the point that I wouldn't feel safe driving it down the highway. Too bad the girl who drives it boyfriend is a bum and doesn't have a job, so she can't afford much else. If that was my girlfriend, I wouldn't let her drive that POS down the block, let alone anywhere else!

Car rule #1: Live in girlfriend/wife shall ALWAYS drive the nicer car, if two cars are owned by said couple who co-habitate within the same domicile. If only one car is owned, the man shall walk/bike/ride the bus until he is able to "man up" and get a decent job that affords the privilege of driving an automobile.

 

[Cutehumor]

I wonder how much a dealership would have charged her to put gas in the car. $150 for "diagnosis"

 

[onion]

Originally Posted By: benjamming
Onion,

Does this o-ring leak result in quite a bit of oil loss? Does anyone make an o-ring for this that doesn't leak at all, not just less?


Said oil pump drive o-ring can be a very significant leak when it fails. And I guess the "leaks less" was poor phrasing in my part- should have said "less prone to leakage". If you fix this leak properly with the new GM o-ring, it will eliminate the leak indefinitely. This new-style o-ring has sealed the oil pump drive perfectly for years in my own '94 Corsica.