jeepogeek

You are probably right but I'm not the sharpest knife in the drawer when it comes to this stuff. I'll get it eventually. This is the first computer vehicle that I have ever worked on. I'm much better with cars of say, the 60's. But I'm usually pretty patient and will persevere. In the end, it's a learning experience for me. How much for the sensors you have since all I'm able to find locally are Denso? Thank you

Okay thanks anyway. That O2 sensor looks like the original so I'm going to replace it anyway as long as I can get it off the exhaust. Probably will need to use heat on the pipe since running the engine up to temp didn't work.

So I think it's in open loop but I'm not sure. Like I said all this technical stuff is rather sketchy for me. I'll check it again if you can help me learn which buttons take me where.

Unfortunately I haven't mastered the REM yet but I will try to get that for you.

Well, there is quite a bit of oily crud stuck to the block, but, for me, thats pretty normal for an engine this old. when I rev the engine to WOT it sounds pretty strong. Like the stumbling almost goes away. Conversley though there is quite a bit of clatter from the valve train at idle. however, it always starts right up. not that that has anything to do with the problem at hand. I'm about to change the O2 sensor and CPS. Best I can tell these guys could have an effect. but who knows? What do you think?

Please elaborate on your idea as I am unfamiliar with it. when you said you thought the truck hadn't been serviced in a long time; I'd have to agree with you. All the components and sensors I've looked at thus far appear to be original. with over 230k on the clock, to me, its probably time to change at least the sensors that could be the cause of rich running. So tell me more about your "steam clean idea" please. Thank you.

Thanks for the ideas and commentary everyone. Eaglescout526 what do you mean steam clean method?

Yeah, walk me through the upload because I tried to do it with my Iphone and it said the file was too big. If you read this whole topic you can find what I've done thus far. However to answer, the plugs are RC12LYC Champion. And I've replaced the cables, cap, plugs, all the fuel pump components, and rebuilt the entire TBI. It doesn't really smoke much just rich carbon smokey stink. It stumbles at all speeds. It sat for at least a few months. I've seen the REM video but it confuses me. iphone

Couple things regarding that. The wife of the guy I bought the truck from (he is deployed to middle east) told me the truck ran smooth prior to the fuel pump failing. Then it sat for a few months. Seems to me if the timing was bad the truck would have run badly then. The other thing is it starts right up. However, if the crank sensor is bad the timing would be effected I guess. That's why I'm thinking of replacing it. I do not think any of the sensors on the motor have ever been replaced.

Thanks for the suggestions guys! I'll look into them. BTW, everything in the fuel tank is new so there shouldn't be any issues there plus I replaced all the external hoses and the in line fuel filter. Shouldn't the REM point me in the direction of the rich running part of all this? Does anyone know how to use the REM? I'm having trouble With it. I'm a 74 year old! I can get it to work but have trouble toggling here and there. Then I just get frustrated and quit messing with it. Remember, the truck starts right up. The spark plugs all have he same dry carbon and the exhaust smells really bad.

An update on what I've done so far and the truck still runs like me when I get up in the morning...running rich, missing and stumbling. I have pulled the fuel tank and cleaned it out, replacing all the parts inside and the hoses. I've also done the ground refreshing and completely rebuilt the TBI including replacing the injector. I purchased the REM but this old guy (me) can't figure out how to use it aside from pushing the buttons. I guess I start replacing the sensors starting with the O2, MAP and CP. Anyone else have any ideas?

As it turns out, the green wire went to the starter relay not the icm. Truck starts as usual now. There has to be something simple about this rough running condition. The former owner's wife told me today that before it died due to the fuel pump quitting that the truck ran smooth. It sat for months so ethanol may have gummed up the injector or something else in the TB. Oh well, the REM is supposed to be arriving tomorrow. Maybe it will tell me something otherwise I will continue pulling apart the TBI and do a rebuild. If any of you read this and have any suggestions please chime in.

I finished with the fuel tank items that were previously mentioned. The truck still runs like crap. I ordered an REM from nickintime, but I didn't hear back from the guy. So I really can't do anything till I get the REM. today I was poking around under the hood and found a green wire near the ICM hanging loose. While performing the ICM contact cleaning procedure I noticed a spade terminal that didn't have anything attached to it. So I plugged the loose wire into it. When I went to start the truck with the key, the truck started in the power on position instead of the start position. The wiring diagram shows the green/white wire going to the coil/icm. Does anyone have any ideas about this condition?

I ended up tying the top of the pump to the fuel pipe with galvanized mechanics wire by securing it like a twist tie using pliers. Seems to be very sturdy

Okay, thanks. I will definitely see if that will work for my application.

So now I'm back to dealing with the fuel tank. I removed the tank albeit a real pain in the you know what, since it was half full. Got it all cleaned up and ready for the new pump and sending unit that I got a while ago. As it turns out you are right eaglescout526, there is no top bracket on the sending unit apparatus to hold the pump secure. Talked to the guy at MTS and he said folks just use zip ties. I'm not too fond of that idea since it could come loose and fail. I want this to be the last time in my life to have to deal with it. I was thinking of tack welding a tab to the fuel pipe to catch the top bracket and secure it with a screw and nut like original. Does anyone have any other solutions before I bugger the whole thing up?

Okay, thanks. In the meantime I will tackle some of the ground redo's and try my hand at testing some of the sensors.

Hey guys. I decided to take a step back with doing the fuel pressure regulator rebuild, mainly because I need to at least do some of the Cruiser Tips first. I did buy a rebuild kit but haven't broken the seal on the package yet in case I want to return it. Yeah, I'm cheap, but I'm also retired and funds are low. The other reason is, I couldn't detect any fuel squirting from the hole in the TB. So now I am just doing a few things that need to be done as a matter of course. Like the other day I replaced the fuel filter and now I'm contemplating dropping the fuel tank to dump out the old gas and install the new fuel pump and associated parts that I already purchased. Question: should I start a new thread since my troubles are not fuel pump related anymore? Also, Is dropping the tank that difficult for an old timer? Thank you for all your comments.

Thanks. I'll let you know how it goes.

Thank you . At the moment I'm interested in the fuel pressure regulator since indications seem to be pointing to fuel delivery as the problem. So where would you suggest I get those parts?

Thanks for the vote of confidence. I'll do my best to get this thing on the road again. In regards to the parts for the fuel pressure regulator, the sensors, etc., what is the best source for that stuff?

Thanks guys for the suggestions. I guess I need a repair manual for the truck. Can anyone tell me what manual they would recommend for this rich running situation that I have? Wow! Thank you very much for all this information. As a mere fledgling mechanic with very little later model car experience it will be difficult to wade through this much material. But I want to try to do it anyway. The last bit of rebuilding I did was to rebuild a Rochester Quadrajet carburetor. which actually came out great. But these engines with computers are intimidating to me. I hope the TBI book goes into the fuel pressure regulator rebuild and I don't have to have a bunch of specialized tools and knowledge. I really appreciate all the advice. I definitely need it.

Thanks guys for the suggestions. I guess I need a repair manual for the truck. Can anyone tell me what manual they would recommend for this rich running situation that I have? Thanks derf. Yeah, I do have the factory manual too.

Thanks guys for the suggestions. I guess I need a repair manual for the truck. Can anyone tell me what manual they would recommend for this rich running situation that I have? Thank you very much for the explanation. I won't be getting the TBI book for who knows how long since the mail seems to be screwed up sometimes lately. But I'll look into it. I just put new Champion plugs in to no avail but I didn't think they would cure the rough running. I did notice the one's I removed were wet with fuel on one side of the base so I guess that confirms that the engine is receiving too much fuel. Let me ask you, are these motors notorious for acting up this way? Something I noticed too was this. when I put the key to power on, the tach goes to 1000 rpm. Then when I go to start the engine, the tach mic's out all the way to the right and the TEMP gauge wiggles crazy like all wacko. Does that tell you anything? I have no lamps on the dash lighting either.

Thanks guys for the suggestions. I guess I need a repair manual for the truck. Can anyone tell me what manual they would recommend for this rich running situation that I have? Did I say something? How do we know that theTPS is in good shape?