87 Wagoneer stalling/stumbling

[bdrainy]

Hi all, new to the board and new to owning a fsj. I just picked up an 87 grand Wagoneer with the 360 and Howell fuel injection set up. Ran great when I test drove it. Did great on the highway for the 2 hours back home, but when exited the freeway and came to a stop... it developed a stumble when I hit about 20 mph.

It will take off fine from a dead stop, but around 20 mph it starts stumbling and has stalled a couple times. I can pump the gas pedal through it and it will catch and be fine cruising. But if I come to a stop... the whole process repeats. I found the tps looked a bit scorched on the bottom so I replaced it, but the problem continues. I also threw a spare coil I had on just for good measure with no change.

The check engine light that was installed does not come on when this happens...I called Howell and they said if the light is not coming on then it’s likely something else. I understand the ICM on these go out frequently...?

Any help would or guidance would be appreciated! Thanks -Brian

[tedlovesjeeps71]

Check the fuel filter? Could be that it’s got some floaties in the tank causing it to stumble?

[bdrainy]

Thanks! Yeah, will check that.

[Shwag]

Tony (aka BabyWag) helped me trouble shoot a similar issue. It ended up being the Ignition Control Module. BTW, I also have the Howell setup.

[bdrainy]

Thanks for the suggestions all. I found the issue and I feel a little stupid about it. The fuel level was too low in the tank and the pickup was coming uncovered. My gauge was reading a quarter of a tank...so I guess my gauge is about off! I filled up and the people completely went away. Thanks again!-Brian

[tedlovesjeeps71]

The problem may be the picking for the sending unit. If it is a replacement it could very likely be too short. I have the same issue in my waggy. I think there is a tread around here that discusses it more. Not sure if a correct length replacement part was ever identified or not. I just extended mine down about 3”s.

[bdrainy]

I’ll have to pull it and see. Thanks for the heads up.

[bdrainy]

Just as a follow up for anyone else experiencing similar trouble...it was my fuel pick up. I finally got around to pulling up the carpet and found that the access panel had been duct taped back in place, so I knew right then the sender had been replaced. Pulled it and measured and the bottom of the pick up tube was roughly 3" off the bottom of the tank. So I got some submersible efi fuel hose and a fuel strainer (linked below) and the problem seems to be solved. I am currently down to a 1/4 tank with no signs of fuel starvation. Now I just need to figure out how to get better MPG out of this thing!

Thank you all for your help!

https://www.summitracing.com/parts/ABT-TF268

[will e]

Welcome to the forum. I am glad you got your issue resolved. Nice work! As for fuel mileage, there is only so much that can be done with a over weight brick shaped behemoth with no over drive.

Shoot for around 10 mpg or a bit more. Some folks on the board will claim higher. Driving style will have a lot to do with it. Keep it at 55 or 65 on the highway when ever possible.

You can do fuel injection and over drive transmissions. These will help some but most likely won't pay for themselves in the long run.

What are you plans for the truck?

[bdrainy]

Thanks! I was hoping for about 10 mpg but currently getting around 6 mpg. My plan was to have this share responsibilities as my daily driver with my 65 Mustang. I just picked it up a few weeks ago and it has the Howell TBI already installed (not sure I am loving it) and 2.5 Alcan lift springs with Rancho shocks (RS5000). It rides way too stiff...not sure if it is the shocks or the springs but plan on addressing that soon.

My plan is really to just drive it and chip away at the little things it needs here are there. (new woodgrain, interior to be freshened up, possibly bring it back down to stock height, etc..) I really got it as a cruiser. I'd like to modify it for more power but am pretty limited being in CA and dealing emissions on it. Attaching a picture...if it works.

[will e]

Yeah, 6mpg is pretty bad. I am a bit surprised since you have TBI. Post up in the 'fuel injection' section about your gas mileage and you might get some help. I run a holley truck avenger on big tires and get almost 10mpg. You should be able to do the same.

I also have alcan springs, mine are about a 1" lift and I find the ride to be very smooth.

Let's here a bit more about the mustang too! I have a 73 convertible hobby car. I have owned it since I was about 20. 351C, C6, gear vendors, tripower, headers, 3.50 gears and traction bars,

[bdrainy]

Thanks, will definitely post over there. I just swapped out my tps as I pulled it and noticed that it had some heat (possible scorch marks) on the bottom. We will see if that helps. I also have a feeling that my clutch fan is staying engaged the whole time. So I will likely inspect/ replace that also.

Your mustang sounds nice! 3:25 or 3:50 gears is on my list. It’s a 65 and originally a 289/c4 car. It currently has a 68 302 with early 289 ported iron heads. I built the motor to be fairly mild and backed it with a T5 from from a 95 mustang. With the original 2.80 gears and the T5 I can cruise at 70 mph down the highway at 1900 rpm.

I also have a 1970 Plymouth Roadrunner. It’s a low option 383/727 bench seat car. It’s running the original 383 but with edelbrock aluminum heads and a few other goodies.

Both cars have been in my family since new and my kids are already calling “dibs” on which one they will get! I have a car “problem” much to my wife’s dismay. She wasn’t super happy about me picking up the wagoneer...but I just could resist!!