ChallengeTheSea

Hello everyone. I've been lurking for awhile but now I need some help. (Have to say I love yotatech by the way!)

Anyhow, my truck has run fairly decently lately, aside from occassional difficult starting when cold. It has always been reliable though, getting me where I need to go without too many problems.

Yesterday though (Friday the 13th!) I drove out to see some friends. It's a fairly long (45 mile?) drive. The truck ran fine at first, but about three quarters of the way there it began to feel strange. Before I knew it the truck was stalling at intersections. While driving, giving the gas a good push the engine would stumble and sputter and the car would shake, becoming barely drivable. Soon it worsened and the car would stall while coasting down hills.

I parked it in a safe-ish spot for awhile, let it cool off, and tried to get over to my friend's place. It seemed to run somewhat well this time, and I managed to get there, although I could feel it wanting to stall on and off, and it lacked a good deal of power.

I've talked to some people and am told my problem could be the fuel pump or filter. Replacing the former seems to be an expensive(I think?) and daunting task. I'm concerned about driving this thing home later this weekend. I'm just curious if anyone might know more about this condition, if perhaps it might be something more simple?

Anyhow, the only thing that has been different with the truck lately is the starter flaked out a few days ago, and would only work sporadically. I replaced it just yesterday morning. I can't see how that could be related to this new problem.

I'm driving an '88 p/u with the 22re and a 5spd. The plugs and wires were replaced last month. Thanks.

Yota4runner

How olds your cap and rotor? It could be a fuel issue, How does it run at idle?

javadoody

sounds like a classic fuel filter issue. start there.

ChallengeTheSea

Not sure how old the cap and rotor are. The car has 250,000 miles on it, but I've only owned it for a year. I did take a look at the cap and rotor in an automotive class I had and we all thought it looked okay. The car starts up nicely cold now and runs fairly well until I drive it too long. I drove it about six or seven miles today and it seemed fine. It idles well until it gets too hot it seems like. I'm not sure if this is just more of a random issue or not. I might try to replace the fuel filter before I think about the drive home.

trythis

it also sounds just like an ignition coil.

ChallengeTheSea

Well, a week later and I'm still having problems.

I replaced the coil and fuel filter and while the truck seems to have more pep and is idling much better it still craps out when I really step on the gas too quickly. But when it isn't crapping out it feels pretty good!

Anyhow, I jumped the fuel pump in the little diagnostics thingy-ma-bobber under the hood and I could hear it running away. I'm gonna try to check the fuel pressure tomorrow.

What else could cause this kind of condition? It reminds me of when the alternator went out on my old dodge, except it doesn't get progressively worse and eventually totally die. It's just sporadic. Stepping hard on the gas suddenly I can almost hold it at this stumbling/stalling stage indefinitely, until I ease back a bit. I can't always reproduce the problem though. Hmm.

Just for the hell of it, the timing couldn't have anything to do with it, could it? I'm not much of a mechanic, so forgive me if I'm way out there on this.

Snorkeldepth

Compression test? With that much mileage it's not a bad idea. I tried a bunch before i did it and it turned out I had a bad #4. Symptoms were (are) a rough idle and stumbling acceleration to about 2500 rpm.

Yours sounds different. But, it's always nice to know what's happening with compression.

ChallengeTheSea

I've been meaning to check compression. I'll definitely do that tomorrow and let you know.

By the way, thought I would mention that last sunday when I drove home the truck ran without any problems at all. I had run some heet and some kind of fuel and injector cleaner (forgot the name) in it, though subsequent applications have not done squat (not that I expected them to.) I then drove it to school on tuesday and it felt great until the way home when it went screwy again. Dagnammit.

ChallengeTheSea

I just checked the compression. I have 175 psi all across the board with very little variation at all. I have to say I am a little surprised.

Any ideas on how to test the fuel pump? Do I just plug my guage anywhere on the fuel line and jump it in the diagnostics box? I'm afraid I don't entirely know what I'm doing all the time.

For that matter, any idea on how likely it is for the fuel pump to cause this condition?

wholiman

IT sounds exactly like what mine was doing. ended up replacing the injectors, fuel pump. fuel pulsation dampner and fuel filter....about 1600 at my local shop. after all that it ran like a champ.... best ever...

ChallengeTheSea

Fuel pulsation damper? I'll have to look into that....

I'm pretty afraid of messing with the injectors and fuel pump. The injectors in particular look difficult, and both injectors and pump are expensive.

While I'd prefer not to, what about cheaper, in-line fuel pumps or the like? Does it really matter what's in there--as long as the pressure is good? I don't have alot of money to throw around and I need this truck as it's pretty much my only transportation.

As far as injectors go, would they be at fault for something like this? It seems like they might cause a cylinder or something to crap out--but the whole engine seems to want to quit when I romp on the gas. I could be completely wrong though...

84sr5yoty

"I just checked the compression. I have 175 psi all across the board with very little variation at all. I have to say I am a little surprised."

Good God!! That's the exact compression numbers for a brand new 22r(e)!!

"Fuel pulsation damper? I'll have to look into that...."

When fuel pulsation dampers go bad, they leak fuel. If you don't smell any fuel with the motor running, it probably isn't the problem.

You can check the fuel pressure regulator by unplugging the vacuum hose and pulling a vacuum on it (I just suck on the hose). It should hold vacuum. Another way to check it is with the motor running; disconnect the vacuum hose from the pressure regulator. If there is any fuel coming out, it's toast.

I doubt that you have an issue with the fuel injectors, as the problem would be consistent 100% of the time.

As for the fuel pump, they usually die pretty quick. It wouldn't last this long with those symptoms. However, it's not uncommon for the little fuel pump connection at the tank from the the fuel pump to become intermittent with age and high mileage. Good techs will actually replace the connector when replacing a fuel pump. Usually it will act up on bumps and/or left/right turns. By the way, this also occurs with the wiring harness that runs under the upper intake manifold plenum. Over time and mileage, the wires rub against the manifold and start shorting out. For peace of mind, I rewrapped mine with electrical tape the last time I had the intake and throttle body off for cleaning. Both these issues can be found by wiggling/jiggling the wires with the vehicle running.

If you haven’t checked for codes, this explains how

http://www.4crawler.com/4x4/CheapTri...CheckConnector

A few items to check they may contribute to the problem are the TPS and the Air Flow Meter. The TPS and Air flow meter can develop "dead spots" over time. TPS's go out of adjustment over time and can cause problems. The air flow meter isn't adjustable (actually it's, but it never should be adjusted with a stock motor setup) Click below for testing and adjusting the TPS.

http://www.4crawler.com/4x4/CheapTricks/TPS/index.shtml

Testing air flow meter

http://www.4crawler.com/4x4/CheapTricks/AFM/index.shtml

Signal generator: When these go bad, the vehicle will generally start up fine, but stumble/die/run like crap when it warms up to or near operating temperature. It should ohm out at 140-180 ohms. Here's the catch though. You’ll have to test it when the vehicle is acting up because it will show the correct specs when operating correctly, but will show incorrect readings when it acts up.

Igniter: These are tough little buggers to catch when they go bad without completely dying and they’re VERY expensive ($400+) to replace. They will test out fine when working correctly, but rear their ugly head when malfunctioning. These get pretty involved for a novice when it comes to testing them. They will cause very similar symptoms that you’re having when malfunctioning.

I could go and make this post as long as a novel, so check these items first and let us know what you find.

Good luck and happy testing

ChallengeTheSea

Good stuff! Thanks! I've been at quite a loss as to where to look next. This helps a lot. I'll be back when I get a chance to go through it.

Much appreciated!

ChallengeTheSea

Haven't got around to looking at all of that quite yet. I did check the AFM though, and as far as I can tell it's good. I wanted to check the tps, but can't find any feeler guages around here...keep forgetting to pick some up.

However, wiggling the connector to the tps caused an audible difference in how the engine idled (might wanna fix that). But the engine also runs without it connected, and the symptoms I'm experiencing are reproducible both ways. Also, jumping the te1 and e1 (though they are labeled differently on my truck, T and E1 I think) produced the decrease in idle speed 4crawler mentions to check the operation of the tps.

I don't smell gas, but I'd like to check anyways; where exactly is the fuel pulsation damper? And for that matter, what about the pressure regulator? I was looking at the diagram in my chilton's but still can't quite figure out what's what in there. All those hoses!

I wanted to check the connection at the fuel pump, but as far as I can see it is totally inaccessible to me. No matter how I squirm my way under the truck I can't get at it. I want to drop the fuel tank as a last, desperate resort--if I have to--so maybe later...

As for signal generator and ignitor, I'm not sure where those are at either. Neither my haynes nor my chiltons talks much about them (well, my chiltons has almost disintegrated...) Is the ignitor that little box on top of the ignition coil?

And just for the hell of it, I pulled my plug wires and tested their resistance. The ones to cylinder 2,3, and 4 all measured exactly the same. The wire to cylinder 1 had a substantially higher resistance though. I have no idea if that is normal or not, but I remember bad wires caused big problems for me in the past, so who knows...

Anyway, I haven't really done as much as I had wanted, but times' been scarce (night classes!). Hopefully this weekend I can make a more serious effort.

ChallengeTheSea

Well, don't know how I missed this earlier...

http://img460.imageshack.us/img460/5099/p10106575zb.jpg

That don't look too good

95ToyotaPU007

looks like the motor does have 250,000 miles on it.

ChallengeTheSea

I'm not actually exactly sure what I'm looking at. Timing chain has broken through...something(?) I've never done any internal engine work (or so much as taken off the valve cover), so I don't really know what this means (besides pain). I've only been messing with cars for little over a year now, so I don't know a heck of a lot.

PirateFins

You might have the infamous 22re timing chain rub thru. Take off your valve cover and have a look down there at you guides or possibly lack there of. Do a search on here you will find a ton of info on how to replace it. Not a hard job at all, just takes some time. Took me about a weekend the first time, but I could do it in a day if I had to. Here is a link for the 93 FSM page on the timing chain replacement so you can see what you can expect. I didn't have to drop the oil pan I just removed the bolts from the bottom of the chain cover. Get the replacement cover and guide kits from www.engnbldr.com , or look for one of his auctions on EBAY. Make sure you get the metal backed guides. Once you get this done you'll be back up and running.

ChallengeTheSea

I like how those two hoses coming out of the firewall back there are located such to facilitate easy removal of the valve cover...

cricket

My vote would be injectors: I recently pulled and cleaned the injectors in my '93 3VZ-E. It only has 85,000miles, but the injectors were really dirty, and I was experiencing a lesser version of what you are. (See my post in the general truck tech).

It's a bit tricky to pull the injectors, but it beats paying $225 per injector to replace (not including labor). I also called my mechanic and they usually do an "on-vehicle" cleaning which involves attaching a pump to the fuel rails and forcing cleaner through the injectors. This is a lot cheaper than pulling the injectors, but may not be as effective.

But there are a lot of other things it could be too...

Crick