Trouble starting, trouble running - Toyota Nation Forum : Toyota Car and Truck Forums

joesrcool · 12-30-2007, 03:49 PM

Ok, I've tried searching other threads, but could not find any of the same symptoms my car has right now.

So, it all started off one day when I came home. Turned the car off, went inside for 15 min, came out and it wouldn't start. It would turn over, again and aigain and again, but would not start.

So, to the diagnosis. The distributer, cap and rotor were replaced 1.5 years ago because it was doing the same thing. So this is what I checked first. So, I pulled each spark plug out and checked for spark one at a time. Everything was good, good strong spark on all.

Next, I moved onto fuel. Bought a new fuel filter and put it in. Went to start it and it started right up. Let it idle for a little while, all was good. Then, I went to go take it around the block and it died in about 500ft.

Now, the car will start almost every time I try to start it, but it starts stuttering at low rpm. Above 1500rpm it won't stutter, but bellow that it'll die after a couple minutes or so. Also, I can gradually raise the rpm just fine, but when I mash the gas it will immediately die. I then took the air filter off because it looked dirty. Started right up, and idled perfect, until I started playing with the gas, then it died.

It seems to run better under cold starts, but once it's all warmed up, it just won't stay running on its own. I can't drive it anywhere, it will die under a load. I'm not getting a check engine light either, but I know it works.

So, what could it be? Fuel pump? Bad gas? Water in the tank or lines? How would you go about other diagnosis's? What else can I check?

Edit: Car has 195,000 miles, 5SFE 2.2l

Thanks,
-Joe

dc_98_cam · 12-30-2007, 05:12 PM

It must be fuel or air intake related ... or maybe a loss of compression.
What are the choices?
Throttle position sensor?
Idle air control solenoid?
Throttle body?
Air intake temperature sensor?
Fuel pump ... or pressure?
Engine compression?

Get a spray can of starter fluid ... give a one or two second burst into the air intake and see if it sounds like it wants to run .... If so, then you have narrowed it down to a sparse fuel condition.

Mike Gerber · 12-30-2007, 05:15 PM

I would check the following things in this order. 1. Fuel pressure (could be a weak pump or a bad fuel pressure regulator), 2. Coil inside the distributor, and 3. coolant temperature sensor (Toyota calls this the ECT sensor). I'm including the coolant temp sensor since you said it seems to run better cold. The sensor could be out of range and constantly telling the ECU the engine is cold. This would produce a constant rich mixture; fine for a cold engine, but too rich for a warm engine. You will need the specs from a manual and a DVM to check the coil and coolant temperature sensor. The manual is stickied at the top of this page. To check fuel pressure you will need a fuel pressure gage and a few fittings.

Mike

dc_98_cam · 12-30-2007, 05:40 PM

If you have a multimeter with a resistance scale, you can check the characteristics of the engine coolant temperature sensor. There is a resistance vs. temp chart in the Gen 4 Diagnostic section of the repair manual .... Might be worth looking into.

DFBonnett · 12-31-2007, 08:49 AM

Based on the symptoms, I'd start by looking very carefully for a vacuum leak, perhaps a vac line that split or fell off.

joesrcool · 12-31-2007, 02:58 PM

I guess I forgot to mention in my original post that the car does run rich when I rev it up gently. Guess that's kinda important.

Quote:

Originally Posted by dc_98_cam

It must be fuel or air intake related ... or maybe a loss of compression.
What are the choices?
Throttle position sensor?
Idle air control solenoid?
Throttle body?
Air intake temperature sensor?
Fuel pump ... or pressure?
Engine compression?

Get a spray can of starter fluid ... give a one or two second burst into the air intake and see if it sounds like it wants to run .... If so, then you have narrowed it down to a sparse fuel condition.

The car does start, sometimes. It takes it a second or two when it does, and kinda sputters until it gets running.

Quote:

Originally Posted by Mike Gerber

I would check the following things in this order. 1. Fuel pressure (could be a weak pump or a bad fuel pressure regulator), 2. Coil inside the distributor, and 3. coolant temperature sensor (Toyota calls this the ECT sensor). I'm including the coolant temp sensor since you said it seems to run better cold. The sensor could be out of range and constantly telling the ECU the engine is cold. This would produce a constant rich mixture; fine for a cold engine, but too rich for a warm engine. You will need the specs from a manual and a DVM to check the coil and coolant temperature sensor. The manual is stickied at the top of this page. To check fuel pressure you will need a fuel pressure gage and a few fittings.

Mike

I'm going to try checking those things today. My question is, would the ECT sensor cause it to not start at all, and cause it to have a hard time starting when it does?

Quote:

Originally Posted by JJJJJJ

I had exact same symptoms with alternator on way out.

You could also try new tank of gas.

I thought about draining the tank and putting new gas in, but it ran fine for the 100 or so miles prior to on the same tank.

Quote:

Originally Posted by DFBonnett

Based on the symptoms, I'd start by looking very carefully for a vacuum leak, perhaps a vac line that split or fell off.

One of my friends recomended that. I'll take a look at them today.

I'll see if I can post a quick video of what it's doing, so you guys can see for yourselves.

Thanks for the help so far,
-Joe

Mike Gerber · 12-31-2007, 04:44 PM

"I'm going to try checking those things today. My question is, would the ECT sensor cause it to not start at all, and cause it to have a hard time starting when it does?"

My answer to that would be possibly. I guess it would all depend upon how far out of range it is. It could be making the mixture so rich it would be like trying to start a flooded engine. That's not to say it is definitely a defective coolant temperature sensor. It's just one of the things that could cause the symptoms you describe.

Mike

joesrcool · 01-01-2008, 06:42 PM

Ok, I have an update. It still has the same symptoms, but now I know when they're going to happen. The car will start after it's been sitting for a long time, a few hours or more. But, after it's warmed up and I shut it off, it will not start again. And if I let it run long enough, it will eventually kill itself. I can also floor the throttle on a cold start and it's fine, but when I do the same when it's warm, it'll just kinda bog down and die.

I also checked the ECT sensor, and it's resistance was in normal operating range. 4000 ohms before I started it, 280 ohms after it was completely warm. That seems to follow the table in the book.

Fuel pressure was also within range of what my manual says.

I'm completely stumped. I've checked for cracked or missing vacuum lines too. No luck there. I'm probably going to take it to a shop tomorrow and see if they can figure it out.

If you have anymore suggestions, please let me know.

Thanks,
-Joe