'93 Pickup New Engine Problem

[Ando140]

My dad has a '93 pickup, the engine started making a funny noise, so he took it in to the shop. They said it was the pin connecting the piston rod to the crankshaft. So, my dad decided he'd buy a new engine and drop it in himself and call it a learning experience... its been one hell of an experience (not in a good way)... We had my uncle helping out, he's taken out & put in new engines several times. We finally got it all back together in May, and tried to start it. It starts, but only for a few seconds, maybe up to a minute. It's almost like its shutting itself down for some reason. We've checked the fuel pressure and everything there seems fine, the engine just stops. We checked for codes from the computer and all we get is the code that says everything is normal. Anybody got any ideas?

[dsrtrcr01]

Sounds like maybe the Mas air flow sensor. Is this all plugged in tight and correctly? Rare but is it carburated? If so there is a vacum line on the bottom of the air cleaner that must be connected or else it does this exact thing.

[Ando140]

Thanks for the reply, its fuel injected, so no carb problem there, but I told him to check the MAF and see if that could be the problem... any way to tell if the sensor has gone bad or gotten damaged (other than getting a new one trying it... I have no idea how much one would cost)?

[sprj8008]

Put an oil pressure guage on it. If the pressure's low, the ECU shuts down the engine. I had a celica do this when the machinist missed a plug in the oil galley.

[Ando140]

Originally Posted by sprj8008

Put an oil pressure guage on it. If the pressure's low, the ECU shuts down the engine. I had a celica do this when the machinist missed a plug in the oil galley.

Good idea, I'll tell him to do that if his truck doesn't already have one... I don't think it does...
Thanks!

[Ando140]

Originally Posted by sprj8008

Put an oil pressure guage on it. If the pressure's low, the ECU shuts down the engine. I had a celica do this when the machinist missed a plug in the oil galley.

I mentioned this to my dad and he brought up a good point. When the truck starts, the oil light goes off. If there was an oil pressure problem, wouldn't the light stay on, and wouldn't we get a code indicating oil pressure was the problem?

[sprj8008]

I don't know what IBD system a '93 will be running and if the codes will appear. In OBDII the system monitors emissions systems. So you'll see a code if you've lost an O2 sensor or a major MAF miscalibration.

If you look at the process to set the timing, on my old toys, there is a bypass plug to drop the computer into a closed loop and allow you to set timing without influence of sensors and timing management. I might suggest you try this. Following that I'd start looking at mechanical issues.

I would suspect that the sensors were working properly so now that you have an issue I'd look other places first. I'd start with the connectors, making sure the sensors are connected securely and the engine and computer grounds are secure. Then I'd double check the timing alignment, which on a 22RE is a minor process. Then I'd get nervous, have a few beers and start looking at TPS, MAF and O2 sensors. An O2 sensor (the old style) might cause this as it won't show a proper mixture reading until it heats up.

[Ando140]

Originally Posted by sprj8008

I don't know what IBD system a '93 will be running and if the codes will appear. In OBDII the system monitors emissions systems. So you'll see a code if you've lost an O2 sensor or a major MAF miscalibration.

If you look at the process to set the timing, on my old toys, there is a bypass plug to drop the computer into a closed loop and allow you to set timing without influence of sensors and timing management. I might suggest you try this. Following that I'd start looking at mechanical issues.

I would suspect that the sensors were working properly so now that you have an issue I'd look other places first. I'd start with the connectors, making sure the sensors are connected securely and the engine and computer grounds are secure. Then I'd double check the timing alignment, which on a 22RE is a minor process. Then I'd get nervous, have a few beers and start looking at TPS, MAF and O2 sensors. An O2 sensor (the old style) might cause this as it won't show a proper mixture reading until it heats up.

great... this sounds like its going to be more of a pain than it already has been... I think we did do something to bypass the computer for timing & such, but I can't remember... its been awhile since we messed with it... My dad mentioned taking it to a mechanic, so I figured I'd try a last ditch effort to get it to work before we submit...
Thanks again for the help!

[mustang67408]

First thing I would check is the computer ground. It should be bolted to the passenger side of the intake manifold. Where the intake and the plenum are bolted together.
The next thing would be the AIR FLOW METER, this vehicle does not have a MAF. The air flow meter is on thwe drivers side and is a big metal looking box that the air intake connects to. As the air enters the AIr FLOW METER IT MOVES A DOOR INSIDE IT. There is a SPRING on this door that is used to keep it closed. IF THE SPRING breaks it will cause a condition like your describing. Take the AFM off and make sure the door springs back closed if you push it with your finger.The AFM also controls the contacts that make the fuel pump run. You should also get a manual and check the CIRCUIT OPEN RELAY, it controls the fuel pump from inputs from the AIR FLOW METER.
Make sure you have the fuel lines connected prperly to the the fuel filter, it definatly wont run properly if you have them backwards.
There is also anopthe ground wire bolted to the cylinder head on the drivers side just below the piower steering pump, make sure its also connected.
Start here and let us know what you find out.

What did you do to "BYPASS THE ECU"? That doesnt make sense, without the ecu the engine wont run.
The engine will not shut down if the oil pressure is low, it only shuts down when the engine seizes. That was only applicable to the old (circa 1980 vehicles), also make sure the idle set screw on the throttlebody isnt turned all the way in, and make sure all the vacuum lines are installed properly.
Let us know

[Ando140]

Thanks for the help guys, I'll give you an update as soon as I can get my dad to actually work on it... could be weeks...

[wheeling]

Originally Posted by Ando140

Thanks for the help guys, I'll give you an update as soon as I can get my dad to actually work on it... could be weeks...

well i had the same problem before run's for a minuite then die's but when it dose run sounds ok it will rev up then die. so if this is the problem. there is a ground wire for your injectors it will only put gas in when u first turn key then will stop. i missed it while i put in my new engine so u should check that out. mine was supost to be by the theromstat houseing but waas not connected.

[Ando140]

Originally Posted by wheeling

well i had the same problem before run's for a minuite then die's but when it dose run sounds ok it will rev up then die. so if this is the problem. there is a ground wire for your injectors it will only put gas in when u first turn key then will stop. i missed it while i put in my new engine so u should check that out. mine was supost to be by the theromstat houseing but waas not connected.

We'll check that one out... believe it or not, its still not running (though we haven't worked on it for awhile). Thanks for the info.
And yes, what you described sounds exactly like the problem we're having.

[Ando140]

Originally Posted by wheeling

well i had the same problem before run's for a minuite then die's but when it dose run sounds ok it will rev up then die. so if this is the problem. there is a ground wire for your injectors it will only put gas in when u first turn key then will stop. i missed it while i put in my new engine so u should check that out. mine was supost to be by the theromstat houseing but waas not connected.

Well, we looked at it... that ground wire (and every other ground wire we could find) were already attached. We even verified continuity using a multi-meter...
Wouldn't happen to have any other ideas, would you?

[wheeling]

Originally Posted by Ando140

Well, we looked at it... that ground wire (and every other ground wire we could find) were already attached. We even verified continuity using a multi-meter...
Wouldn't happen to have any other ideas, would you?

well did u make sure that the computer was the right one for that engine if the engine and truck r both from 93 it dose not mean that they r right together. some times it may say 93 but could be from 92 or 94 . this is rare but u never know. now u could also try this out to see if it will run alittle longer . now on the efi systems there should be or might be a cold start injector on the intake. find the power side of the wire going to the cold start injector. now make a small slice just so u can see the bear wire. with out starting it yet connect a wire from it to the power side of the battery (for like 2 seconds ). u should hear a click. if u do good. now get ready to start it. just before u roll the engine connect the wire and hold it there then start it. this will keep gas flowing . if it says running with the wire being heald on, u have a gas flow prolbem. (it will run rough )if it says going. if it dies then i will think of something else to try. make sure u tape up bear wire after done. by doing this and holding it on to long u could floud the engine so be careful of how long u hold it on. even if it is turned off there is still presure in the gas line. if it runs for 5 min that should be good so u know more what to look at..

[Ando140]

Originally Posted by wheeling

well did u make sure that the computer was the right one for that engine if the engine and truck r both from 93 it dose not mean that they r right together. some times it may say 93 but could be from 92 or 94 . this is rare but u never know. now u could also try this out to see if it will run alittle longer . now on the efi systems there should be or might be a cold start injector on the intake. find the power side of the wire going to the cold start injector. now make a small slice just so u can see the bear wire. with out starting it yet connect a wire from it to the power side of the battery (for like 2 seconds ). u should hear a click. if u do good. now get ready to start it. just before u roll the engine connect the wire and hold it there then start it. this will keep gas flowing . if it says running with the wire being heald on, u have a gas flow prolbem. (it will run rough )if it says going. if it dies then i will think of something else to try. make sure u tape up bear wire after done. by doing this and holding it on to long u could floud the engine so be careful of how long u hold it on. even if it is turned off there is still presure in the gas line. if it runs for 5 min that should be good so u know more what to look at..

Is there any easy way to tell if the computer is correct?
I'm not sure if my dad will be willing to go cutting into the wiring on his truck, but I passed the info on to him. I'll let you know if he tries it, I know he won't have time until at least tomorrow.
Thanks for the help.