4.3 TBI fueling issues

Plugs/wires are in the correct order and yes 1-6-5-4-3-2 is the correct firing order. I’m assuming the timing connector is in the engine harness? Everything I have seen online says there is a connector that you can unplug. I still need to locate that wire. It’s very apparent that the engine is flooding with fuel. Spark plugs are wet and reek of gas. If I pull the plugs and let it air dry I can usually get a fireball out of the exhaust at the first startup. I set the timing at 0 at TDC on cylinder 1 and the rotor was pointing to the 1 post on the cap. The timing should be correct?
 
Yes thats right on the distributor. The connector is in the harness somewhere some were under the hood near dist and used the same style as plastic part as the o2 sensor, some were under the dash about 6 to 12" from the computer, not sure what your harness is from.

If you didn't spin the motor or blow air into the plug holes to dry the cylinders out it could have refouled the plugs. Also I have seen plugs get so gas fouled they will not run in an engine ever again. Not sure why that happens.

If the wires are right and in time and it has fuel and fire it will run. The only other thing to check would be to pull a valve cover and verify the cam is in time. But I'm going to stick with its just that flooded for now.

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I have had fouled plugs work after I cooked them with a torch.
 
I have my running 4.3 here if you need to do any kind of comparison testing? There is a switched power wire that goes to/powers the PCM that I would assume you know of? I used a Howell harness so it was all marked.
 
It sounds timing related for sure. Just because you have the timing mark at 0 and the rotor pointed at number 1 on the cap doesn't necessarily mean your timing is close enough. With timing mark @0 #1 top dead center, rotor needs to point at number 1 on the dist. cap, and line up the reluctor wheel points in the distributor base under the rotor. If the points (peaks of the star) on the wheel line up, then you should be extremely close to 0*.
 
For timing, I have only lined up cylinder 1 at TDC and the rotor button to 1. I did not realize you could move the reluctor points. I will recheck TDC tomorrow but it should be extremely close(close enough to fire anyway). I'm using the second mark on the crankshaft to align TDC. The plugs do not look to be fouled at all. They are just wet with gas etc. I've spot checked them and they all still fire. My plan for tomorrow is to pull both valve covers and spin the engine to make sure all the valves are opening/closing. Then i'll play with the timing. Will update with any new info tomorrow.
 
After looking at a bunch of pictures online, I think I have the timing set to 6 degrees. The timing marks are pretty well rubbed off and what I thought was 0* was actually 6*. So, I will have to retime the motor and pull the distributor. It's a pain in the ass to pull it because of the clearance with the firewall but hopefully this fixes the issue.

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Another way to verify tdcc #1 is to pull the plug, install the hose from a compression tester or plug with a finger. Bump the motor while holding finger over hose end or sticking finger in plug hole. Bump starter until it starts pushing your finger off or out. Then rotate engine manually CW until you reach 0*. There's a wire to disconnect to set timing without computer advance (normally on pass side, under heater box near top of carpet. Gray/black IIRC)
 
So setting the timing to 0 instead of 6 didnt make much of a difference on the rotor. Note the sharpie mark on the distributor. That is a reference line for post 1.

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Now the reluctor points do not line up at all. I have a small amount of play in the reluctor but don’t see any way to rotate it. Is there a way to rotate?

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Last picture is showing the second mark on the crankshaft at 0 degrees

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Some of the plugs had some gas in them. I’ve pulled them and going to let them air dry and then hit them with a propane torch before reinstalling.
 
You need a distributor, That thing is shot. The reluctor points are lined up like they should be in that pic showing all the rust. Lock that distributor down there, put rotor on and put number 1 cyl on whatever spot the rotor points to. If it is in between spots on the cap then you need to rotate a tooth forward or back. If you get up to mooresville at all I'm pretty sure I have a good 4.3TBI distributor you can have, you need one.
 
So even with good spark, the distributor would be bad as it can’t set or advance timing correct? If you have a good distributor, I can make the drive up tomorrow. What’s your drink of choice?:beer:
 
That wheel is the pickup for the timing. So with all that rust, just like an ABS speed sensor it can skew the pickup. When the points on the wheel line up is when the coil should fire, but the rust and any play in the distributor shaft can cause it to read incorrectly. From the looks of it, the shaft bushings aren't going to make it much longer. If you are getting spark and fuel, then the timing must still be off, but that could be due to all the crap in that distributor. I will pm you my number, I should be at the shop most of the day tomorrow.
 
Picked up the distributor from @NC-V and the jeep cranks and runs....kind of. I think it’s dumping to much fuel into the motor. If I pull one injector harness off, the motor will start on starter fluid and run very rough. If I try and plug the second injector in, the motor immediately cuts off. Could it be the fuel pressure regulator stuck wide open? Coolant temp sensor?
 
Yes to both. Check fuel pressure I'd look for 10 to 13 on a stock pump and chip. If it's been tuned then who knows.

Inspect temp sensor wiring for corrosion and compare the sensor to this chart with an ohm meter.

Also you did get injectors for a 4.3 right? The v8s had larger injectors.
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On the advice of @NC-V I rotated the distributor while the Jeep was idling and it smoothed out. I was able to install the second injector and it runs now. No O2 sensor and only headers so it sounds like a tractor and idles pretty rough but she’s running! Big thanks to everyone here for the info. @Tim C I owe you some beers.
 
Also a low vacuum reading by the map sensor will go rich, make sure the vacuum line has vacuum and isn't knocked off

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Awesome news. Set the timing with a light asap. Unplug the timing wire, then crank it and turn dist to 0 most likely stock, but 0 to 10 will work, then reconnect the timing wire.

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R Q said:
I know a guy in Rock Hill that can tune it and burn a new chip if needed.
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Caver Dave said:
Or an old computer/laptop (w/ DB9 serial port), a $5 DIY cable, and WinALDL will tell you everything you need to know and more...
Click to expand...

I have a winALDL and a few different programs, so I can see the variables and I can adjust timing and fuel pressure, but I am not sure how to make adjustments to the fuel maps or what have you. I feel like I have a bit of power left on the table that I really need to fine tune for. Any particular programs for that, or @R Q , who's your guy in Rock Hill?
 
paulevans76 said:
I have a winALDL and a few different programs, so I can see the variables and I can adjust timing and fuel pressure, but I am not sure how to make adjustments to the fuel maps or what have you. I feel like I have a bit of power left on the table that I really need to fine tune for. Any particular programs for that, or @R Q , who's your guy in Rock Hill?
Click to expand...
I use tunerpro rt it's free to download and use, $30 donation if you want to register it to remove the 10 second nag box that pops up every time you open it. I bought a fast burn 2 from moates for around $90 and use those to burn chips. You'll also want to buy a few chips for $5 each and a zip socket which isn't bad either from www.moates.net

If you're doing tuning you'll either want to modify the stock ecm with a zip socket (which I recommend as its a better connection for off road) or modify a chip (which is kind of ghetto rigged) plans to do either are found in the FAQ sticky thread on www.binderplanet.com fuel injection page or on www.thirdgen.org on the DIY prom page.

The zip socket requires de- soldering the original 24 pin chip socket and modifying a 28 pin zip socket and resoldering. It's not terribly difficult.

Once completed you burn a new chip that copies what you currently have and drive around dataloging with winaldl. There's a dos based program you can run that handles changing the fuel map, I can send it to you or download from a link at one of the above forums. It will take your old table, multiply by the changes needed in the datalog, and give you a new table that you copy onto tunerpro.

If it sounds like something you're interested in there are several of us on the board that have experience with it that can help. I like tuning myself cause I can get it just how I want while driving, Vs paying someone else who will just give a generic tune. For example on my crawler I've got the timing map skewed high at low rpm (it idles at 28 to 30 degrees) which makes it have tons of off idle torque. I tuned it myself with no spark knocking, a generic mail order tune won't have as much timing since they aren't there to hear the knock.

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Tim C said:
I use tunerpro rt it's free to download and use, $30 donation if you want to register it to remove the 10 second nag box that pops up every time you open it. I bought a fast burn 2 from moates for around $90 and use those to burn chips. You'll also want to buy a few chips for $5 each and a zip socket which isn't bad either from www.moates.net

If you're doing tuning you'll either want to modify the stock ecm with a zip socket (which I recommend as its a better connection for off road) or modify a chip (which is kind of ghetto rigged) plans to do either are found in the FAQ sticky thread on www.binderplanet.com fuel injection page or on www.thirdgen.org on the DIY prom page.

The zip socket requires de- soldering the original 24 pin chip socket and modifying a 28 pin zip socket and resoldering. It's not terribly difficult.

Once completed you burn a new chip that copies what you currently have and drive around dataloging with winaldl. There's a dos based program you can run that handles changing the fuel map, I can send it to you or download from a link at one of the above forums. It will take your old table, multiply by the changes needed in the datalog, and give you a new table that you copy onto tunerpro.

If it sounds like something you're interested in there are several of us on the board that have experience with it that can help. I like tuning myself cause I can get it just how I want while driving, Vs paying someone else who will just give a generic tune. For example on my crawler I've got the timing map skewed high at low rpm (it idles at 28 to 30 degrees) which makes it have tons of off idle torque. I tuned it myself with no spark knocking, a generic mail order tune won't have as much timing since they aren't there to hear the knock.

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Click to expand...

Cool cool - thanks for the detailed response. Sounds a little out of my current depth, so I have some reading to do, but that sounds like a worthy time investment to have something that will run like I want it to. I have enough money, sweat, and time into my motor (a TBI fueled GM 3.4 in place of the old 2.8), I hate to be disappointed in it.
 
paulevans76 said:
Cool cool - thanks for the detailed response. Sounds a little out of my current depth, so I have some reading to do, but that sounds like a worthy time investment to have something that will run like I want it to. I have enough money, sweat, and time into my motor (a TBI fueled GM 3.4 in place of the old 2.8), I hate to be disappointed in it.
Click to expand...
Binder planet is a international scout website. That's where I figured out how to put tbi on my Ford v8. It has several good threads with details on setting up injection, the only downside would be if photobucket screwed things up. It has a thread in particular in the stickies showing how to mod the ecm like I said. If you have any soldering skill it's an hour job tops.

Thirdgen is a camaro site that has tons of detailed info on tuning, get on both sites and start reading, it's like falling down a rabbit hole.

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Tim C said:
Binder planet is a international scout website. That's where I figured out how to put tbi on my Ford v8. It has several good threads with details on setting up injection, the only downside would be if photobucket screwed things up. It has a thread in particular in the stickies showing how to mod the ecm like I said. If you have any soldering skill it's an hour job tops.

Thirdgen is a camaro site that has tons of detailed info on tuning, get on both sites and start reading, it's like falling down a rabbit hole.

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Click to expand...

I have near zilch soldering skillz, so it will probably take me a month and a dozen brick'd ECMs but I'll get it. Thanks again :D
 
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