SL2 Rough idle/hesitation

[CameronJK]

Hi everyone, new user here. Need some help with my recent purchase:

1997 R title Saturn SL2, 105K miles
99-01 engine, unknown miles (didn't know this upon purchase )
Service (wrench) light is on

Has been sitting in my possession for 2 months, I'm sure much longer before I bought it. If I had to guess, I'd say anywhere from 6-12 months. Gas is definitely old, and at 1/4 tank.

When I bought it, it had a methodical hesitation. Turned out to be the timing chain skipping teeth because the tension plunger was toast.

So anyways, after ordering the wrong kit (91-98) several times, I finally fixed it in my driveway. I'm 95% sure I did it correctly. New timing chain kit, water pump, fresh oil change and new coolant.

Initial startup: Would start, rev around 1000 rpm for a second or two then turn off. Did this 3 times, then I gave it gas upon startup. After a 2-3000 rpm rev for about 10-20 seconds, it started idling without dying-roughly. I took it around the block, it idled around 500-1000 and seemed like it wanted to stall after taking it out of gear. Sometimes it idles good, but once I start moving it'll idle very badly.

So I filled the tank with ~4 gallons of new gas and a can of seafoam before leaving it's parking spot (besides the ride around the block). Started it up and drove to the gas station (1.5 miles). It was hesitating once i got on the main road. Sometimes erratically, sometimes methodically. Then it finally stalled right as i pulled into the gas station. I'm very worried about this because the methodic hesitation is what was happening with the bad timing chain...REALLY don't want to go through that again

That about sums up the info I have..anymore questions I'll gladly answer to my knowledge, and any information is appreciated
Thanks!
-Cameron

[fdryer]

Ever replace the original coolant sensor? While stale gas was refilled with fresh, the fuel filter may be questionable as well as injectors possibly corroded. Fuel pressure should be checked if you have access to one (Autozone loaner). Without replacing the fuel filter, simply disconnecting the output side and either pointing it into a container to catch fuel or attach a length of tubing to feed into a container may help; have someone turn on the ignition switch as the pumps runs for 2 seconds. This short timed event should push fuel out. A pressure gauge will display pressure.

[CameronJK]

Fdryer: Thanks for the timely reply!
I did purchase a new fuel filter but won't be installing it until it warms up tomorrow. I'll go to autozone tomorrow and borrow a pressure gauge if they have it; what should the gauge read? As for the injectors, can I clean them out like any other injector? I've done this on my integra, not sure if it'd be the same procedure.
Thanks again
-Cameron

[fdryer]

Expect to see 40-55 psi and ignore bleed down pressure and when it occurs. Pressure is important as a running engine and normal fuel pump will maintain pressure. Once an engine stops, bleed off occurring doesn't matter. Pressure should remain steady as the engine idles or under load.

I wouldn't pull injectors unless absolutely necessary and you haven't described anything to force injector inspections, yet. Having less than a 1/4 tank of fuel and diluting this with four gallons of fresh should not cause problems since ethanol will absorb condensation and pass it thru the injectors. Using Seafoam should counter condensation too. Worse case scenario is what just occurred one state over from New York; http://www.nbcnewyork.com/news/local...297605201.html. A sample from the gas station showed a jar with 50% water/50% gasoline. This only occurred twice in New Jersey to my knowledge with many vehicles dying as soon as watered down fuel enters the engine. Its not likely to occur anywhere if anyone suspects it because it would leave a trail of stalled vehicles all over the area. I'd be more concerned about checking the easy things first and using process of elimination along with common sense, leaving the hardest things to check last.

[CameronJK]

So today I replaced the fuel filter and spark plugs. The idling problem has ceased, but it still hesitates under WOT. Every once in a while it will hesitate while just revving in neutral. I still have yet to check pressure, I'll definitely do it this week.
Thanks
-Cameron

[CameronJK]

Okay so it's been awhile, I have an update. For some reason, the car just stopped hesitating...what?? I took it for a drive, and seemed fine. Then the next ride was fine too! I thought my worries were over-

But then this morning, I went to take it around the block. It started hesitating again every gear, not a random hesitation but melodically again

So I cleaned up the MAF sensor, and went to go around the block. It wouldn't start at all, but cranked just fine

Any ideas? I'm freakin stumped

[fdryer]

Well, its good forum etiquette to reply to ideas, suggestions, thoughts, opinions, whatever, to have everyone on the same page. Without a reply to post #2, this can lead to chasing a non existent problem or distraction from a sequence of troubleshooting steps.

Your Saturn does not have or use a Maf sensor.........

[CameronJK]

My apologies, totally forgot about the fuel pressure. It checked out, but I haven't checked the coolant sensor. What's the sensor located on the left side of the intake manifold? Whichever that one is, it's cleaned now.
I'll check the coolant sensor next, where is that and how should I go about it

[fdryer]

What's actual fuel pressure? Just saying "it checked out" can be misleading as assumptions are one cause of misleading information. Remember, you're the only one to see and hear what's going on. No one on these public message boards are standing next to you. Without actual pressure numbers, anyone can presume 10 psi is good enough when its not.

The intake air temperature sensor sits on the air intake tube as another input to the pcm for many things. The coolant sensor is next to the egr valve on the cylinder head.