'01 Saturn SL1 won't accelerate when warm

[wingsauce7]

[FONT=&quot]I have a '01 Saturn SL1, 5 sp standard with 325K miles on it. It's been running great until a couple days ago when after driving about 15-20 min, the engine started losing power. Took me about 15 mins to get it into a parking lot off the highway.

I looked for any obvious vacuum leaks, bad spark plug connections, ect. I left the parking lot without ever shutting the engine off and had ZERO issues.

I had less than a 1/4 tank of gas, so I filled it half way thinking maybe bad gas or crud busting loose or water may be the culprit. Got it home after fueling without issues.

Seems like a fuel problem to me, but can't see anything obvious. For the heck of it, i pulled plugs and cleaned/regapped (they were 0.80 in!). I drove it around town trying to simulate the driving I did they day I had problems and it ran fine.

Today I took it to work. After back road driving for 15 min, I got on the interstate and after about 5 miles at I-state speed, it started losing power again. I limped off the road and into a parking lot where a friend picked me up.

Never got a SES light, temp seemed normal, engine never died. I have no trouble codes to go by. One thing I did notice, was it was kind of difficult to change from gear to gear while driving. I got back into the car 2 hours later and drove home the exact route with no issues. Both times I had problems, the temps outside were cooler 70 degrees the first time and about 60 the 2nd.

I have done the following (besides the plugs the other day):
-turned key to run and listened for fuel pump on/off.
-checked the manual trans fluid level which was good.
-removed and cleaned the EGR valve (some carbon, but little dingus moves freely)
-inspected wiring for the eng coolant temp sensor (I replaced this a couple years ago and there isn’t any temp flux when the car acts up)
–checked alternator output volts and it’s good.

Took it out again after cleaning the EGR valve and it failed after 20 min again... POS right now!

I'm kind of at a loss with it being intermittent. I would think a clogged fuel filter would be more constant. Hard to T/S the fuel pump with the intermittent problem too.[/FONT]

 

[JuiceTheGator]

Hmmm. Coil going bad? They tend to stop working when warm when they go. You probably checked the fuel filter already...the obvious culprit.

 

[wingsauce7]

I'm going to put a fuel pressure gauge on it tomorrow and see if I can measure the pressure when it's failing. You'll laugh, but I actually haven't changed the filter. I figure it wouldn't start failing at a certain time/temp and they're $50 fucking bucks for a saturn! Filter should last longer than 325k ,miles shouldn't it, lol

 

[HammerDown]

Can just about guarantee it's something simple. Bad plugs or vacuum loss were my first two guesses. Will be very curious to hear what it ends up being.

 

[fordman84]

What's it sound like? If you start it and idle does it run ok? Does it cut out when trying to accelerate or will it start to sputter?

If the engine is missing we can rule out tranny, if the engine purrs then its the tranny.

I'd put money on a vacuum leak. Gotta be careful doing it, but find a vacuum leak with a can of carb cleaner with the red tube on it. Start the engine, then spray it around the vacuum ports. When you hear the engine sound change, there is your leak.

Not sure if it would be an issue in an '01, but try letting the car idle and pump the brakes. See if that changes your idle speed. A brake booster going out can drop your vacuum and you would have a hard time getting carb cleaner in there to find out. YOu can also vacuum check with a big cigar and lots of time. Turn engine off, take a big drag, then pull a vacuum hose and blow into it. Typically works best with something straight off the manifold. Keep drawing and puffing into the hose until the system is full of smoke and watch for little wisps. Not as quick but more fun.

 

[HammerDown]

I misunderstood and thought he had ruled out a vacuum leak. If not, that is absolutely mt top guess based on these symptoms.

 

[Camfantasy]

I misunderstood and thought he had ruled out a vacuum leak. If not, that is absolutely mt top guess based on these symptoms.

Mine too.

 

[wingsauce7]

Can just about guarantee it's something simple. Bad plugs or vacuum loss were my first two guesses. Will be very curious to hear what it ends up being.

Vacuum leaks were the first thing I looked at on the road. The plugs and wires are good. You're prob right about being something simple, but my gut's telling me fuel pump..

 

[fordman84]

Vacuum leaks were the first thing I looked at on the road. The plugs and wires are good. You're prob right about being something simple, but my gut's telling me fuel pump..

Vacuum leaks are a PITA though, they can look fine but a hairline crack in one will ruin your day. A decent mechanic could also do a smoke test with a machine, or a propane can works too. I'd recommend putting an hour into that.


As to the fuel pump, I'm not sure they are an intermittent issue. Typically they are on or off, not surging like that (unless it is mechanical, again not sure on 2001 but should be electric). A fuel filter perhaps, when was the last time you changed it. If nothing else, might be a good idea with that many miles on it and it is cheap.

 

[wingsauce7]

What's it sound like? If you start it and idle does it run ok? Does it cut out when trying to accelerate or will it start to sputter?

If the engine is missing we can rule out tranny, if the engine purrs then its the tranny.

I'd put money on a vacuum leak. Gotta be careful doing it, but find a vacuum leak with a can of carb cleaner with the red tube on it. Start the engine, then spray it around the vacuum ports. When you hear the engine sound change, there is your leak.

Not sure if it would be an issue in an '01, but try letting the car idle and pump the brakes. See if that changes your idle speed. A brake booster going out can drop your vacuum and you would have a hard time getting carb cleaner in there to find out. YOu can also vacuum check with a big cigar and lots of time. Turn engine off, take a big drag, then pull a vacuum hose and blow into it. Typically works best with something straight off the manifold. Keep drawing and puffing into the hose until the system is full of smoke and watch for little wisps. Not as quick but more fun.

Sounds perfect. Idles great. I changed the intake manifold gasket in this car about 4 years ago due to a vacuum leak that caused really high idle. This is a stalling/no power/no acceleration issue that seriously came out of the blue. Even when it's happening, the car makes no unusual noises- it just won't maintain speed.

 

[fordman84]

Oh, one more thing to check that is notorious for plugging up or developing vacuum leaks...PCV. Should be plugged into the top of your valve covers. Had one pop out on my '84 truck one time and thought I was offroading. Popped back in, ran like a champ. The hose gets hot enough to wear out, or the PCV itself can clog up easily. Supposed to change em every 30k or something dumb, but most people forget them. You should be able to pull it out of the cover with a little force and then tap it. If it rattles, probably ok but again cheap to replace. Look to see if the hoses are cracking on the end, that is a good source for leaks and a leak there wouldn't kill the engine just make it run really rough.

And running with a bad one will blow ever top-end seal you have in there.

 

[wingsauce7]

weird thing is I'm getting no trouble codes or SES light..

 

[wingsauce7]

Oh, one more thing to check that is notorious for plugging up or developing vacuum leaks...PCV. Should be plugged into the top of your valve covers. Had one pop out on my '84 truck one time and thought I was offroading. Popped back in, ran like a champ. The hose gets hot enough to wear out, or the PCV itself can clog up easily. Supposed to change em every 30k or something dumb, but most people forget them. You should be able to pull it out of the cover with a little force and then tap it. If it rattles, probably ok but again cheap to replace. Look to see if the hoses are cracking on the end, that is a good source for leaks and a leak there wouldn't kill the engine just make it run really rough.

And running with a bad one will blow ever top-end seal you have in there.

I'll check that out. How about Crank position switch?

 

[fordman84]

weird thing is I'm getting no trouble codes or SES light..

Yeah, but that 2001 might not have had all the checks that we do now on OBD2. My newest car can tell you which door sensor is out, not even 2008 could do that.


If it isn't throwing any codes, you might also consider reseting the ECM/Computer. Pull the negative battery cable, let it sit for 30-45 minutes, hook back up. My 4runner is terrible about it. If the batter dies or I disconnect, the computer needs about 2 minutes before it can "remember" how to drive forward. Crazy, it will feel like you are driving in 4-low...tons of rev but crawling. Then I remember, put it in park for a minute, then when I put it in gear again off it goes like no issues. DOne that since about 30k miles on it and Toyota dealership swears that nothing is wrong with it.

 

[fordman84]

I'll check that out. How about Crank position switch?

crank and cam sensors typically will throw a code. Could definitely do it, but seems like that would also be an "all or nothing" issue. The intermittent part is the crazy part. Running rough could be anything, but running fine for a bit then not is odd.

 

[JuiceTheGator]

We need more betting on these side issues. I wanna put 20 vCash on a vacuum leak and 5 on a clogged fuel filter as a longshot if the payoff is good enough.

With 325k miles, it could be a lot of very small things. I even had a fuel pump start acting squirrely on an old car when it started going.

 

[wingsauce7]

We need more betting on these side issues. I wanna put 20 vCash on a vacuum leak and 5 on a clogged fuel filter as a longshot if the payoff is good enough.

With 325k miles, it could be a lot of very small things. I even had a fuel pump start acting squirrely on an old car when it started going.

Lol...really, it'd be funny if it wasn't my work beater car. I'm going to plumb in a fuel pressure gauge after work to see if the pump pressure drops off when the car's fucking up. I'll let you know. gonna pull and rattle the PCV valve too.

The car has had a check engine light for about 100K miles(been waitin for that damn light to burn out), but it's been a P410 emissions (secondary air pump). I cleaned shit out out of the metal tube that goes from the air diverter valve to the exhaust manifold. the air pump is working. I don't think this is related to my current issue.

The other code i've gotten over time is p401 the EGR valve not producing enough flow. I've cleaned this valve twice and it seems to be working ok. It may need replaced, but i'm not sure it would cause this issue if it's bad.

 

[wingsauce7]

If I clear out the above codes and drive the car for the 20 minutes or so that it takes for the acceleration problem to start, I don't get any new codes. That's why I believe the acceleration problem is separate from the emissions codes?

 

[wingsauce7]

Checked the PCV valve and it was good. The fuel pressure gauge I was going to borrow only with to 15 psi so it does me no good. I believe my pump puts out much higher than that. I'll check at harbor freight...

 

[CarlWinslow]

a Saturn with 325k miles? time to build a ramp and jump it