Brian's '96

[yikes]

The shocks don't like square edges too well.

Your front's won't ever, the draw back of a position sensitive versus velocity sensitive.

Yeah, I've come to realize that Brian. With all that's invested in getting these shocks under the Bronco, I think I'm going to push it to the next level and take Steve's suggestion to dump the tubes and put a valve stack in them. Bet they will work awesome with a little tuning and run cooler to boot.

[BDKW1]

You could try some stiffer check valve springs in one of the later comp stages. This would let you keep the valve open farther but still maintain low speed damping.

[yikes]

AAAAHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH!!!!!!!!!!!!!!!!!!!!!!!!!!

[yikes]

!@$#$^*^%*&)%(#^&!%&f#u%d^g*e@$%^*#%^*#@%^*($*$^&*^%(^*%&ass@!$^^*s#h@i$t%^%#&$&**

[yikes]

Problem: No power. Stumbles with rich mixture at idle.

What's been checked?:

- Fuel pressure is 32 at idle, 40 at WOT.
- Coil (functional test when in Baja)
- Only code in Baja was O2 sensor. Replaced since then and don't think it was the root of the problem.
- Plugs are all cinnamon in color. One cylinder shows signs of some oil, but nothing wet.
- Intake manifold is dark/wet behind the throttle body.

What's been replaced?:

- New Motorcraft TPS
- New Motorcraft temp sensor
- New Motorcraft fuel pressure regulator
- New Cap & Rotor
- New Autolite plugs
- New O2 sensors (2 fronts)
- New vaccuum lines
- New Standard EGR Valve
- New EGR Control Module


Not sure where to go from here. Any suggestions?

[AussieRod]

I would try looking at the pick up in the distributor, the air temp sensor (and its position), then try another ECU. Hot weather can soon take their toll on them, even Ford ones are not invincible.

[yikes]

I would try looking at the pick up in the distributor, the air temp sensor (and its position), then try another ECU. Hot weather can soon take their toll on them, even Ford ones are not invincible.

Maybe the crank sensor? Hope it's not the ECU, but who knows at this point. Doesn't throw a check engine light anymore.

[SteveG]

Guessing blindly (with no scan data) I'd say maybe the mass air flow sensor. Bad ecu's are rare but I think I still have one. It's yours if you want it.

[SteveG]

Maybe the crank sensor?

Doubtful. They generally work or they don't. An intermittent signal might cause an intermittent hiccup or no-start but not a rich condition.

[yikes]

Guessing blindly (with no scan data) I'd say maybe the mass air flow sensor. Bad ecu's are rare but I think I still have one. It's yours if you want it.

The MAF sensor didn't pop up on the scanner (in Mexico), but I wouldn't doubt it. It's been abused plenty. As for the ECU, that would be great Steve! I'll take you up on that and cover shipping. If it's not the issue, I'll send it back.

[damon1272]

I would say steve is pretty close on the MAF sensor. They don't tend to code but dust kills them. One other item that tends not to code up due to large parameters is the map/bap sensor. They will cause a rich, no power situation like you stated. cheaper easy try than a maf sensor.

[AussieRod]

I believe we swapped the MAP to try at HP Ranch. Brian?

[SteveG]

The MAF sensor didn't pop up on the scanner (in Mexico)....

No sensor is just going to stand up and say "I'm bad! Replace me!"

There is a big misconception that fault codes point directly at the failed part. For example, if you have a code for an Oxygen sensor being out of range, it doesn't necessarily mean the sensor is bad. What it's telling you is that the ECM is seeing a signal that is not within specified parameters. If the sensor is showing a lean condition, either the sensor is bad and won't read rich or there truly is a lean condition and the engine can't compensate for it... indicating a problem somewhere other than the sensor itself.

The mass air flow sensor (again, just an example) could be telling your ECM that the truck is at a completely different altitude than it really is, causing the engine to run an air/fuel mixture that is nowhere near what it really needs.

Buy this book. Unfortunately, it doesn't cover your truck directly, but all the same principles apply and the all the sensors are virtually the same as what your truck uses. Read it front to back and learn all kinds about what it takes to make these systems work.

[philofab]

Fix your IAT sensor location. Being out of the intake flow is bad.

I wouldnt be surprised if it's your MAF. I'd take a crappy vane sensor in the desert over a MAF any day. That's why I prefer MAP only systems for dusty conditions.

[Dust]

Pull the MAF and clean it. Takes what maybe 10 min, then go drive it and see if it did the trick total time maybe 30 -min.

[yikes]

I believe we swapped the MAP to try at HP Ranch. Brian?

Doesn't have a MAP sensor in '96. I read Ford realized there was no benefit and stopped using it.

Steve - That book is downloaded to my computer now. Thanks man! I'm sure it will be a good reference while I figure this electronic bologny out. Miesk5 sure has some good stuff linked out there.

Dust - Yeah the MAF has been removed and cleaned many times. It's been somewhat routine since I've used the K&N. Haha! But all eyes are on it now. I pulled it again this morning and looked at the pick-ups or whatever they're called with an eye loupe. They're not broken, but the leading pick-up was not straight. Slightly bent. Now, I recall it being like this for a couple of years. Perhaps I bent it a long time ago. Not sure, but as gently as possible (after a strong cup of coffee), I massaged it back to parallel and put it back in the housing. The Bronco ran all day! I've been out 4 different times and put a good 100+ miles on it today. No stumbling or loading up. It's still a bit down on power, but it's working ok.

I've never been much into the electrical side of things, so I don't even own a multimeter, but I will before long. That being said, I have not identified precisely why the MAF is working okay now. Or whether that's even the problem. (By "okay" I don't me correct). Could have been coincidence. Maybe there's a bad signal from a wire that fixed itself when the sensor was unplugged and re-attached. It's too expensive to just buy a new unit without solid justification. If bad, this is one sensor I'll be going directly to Ford for, unless there's unanimous agreement on another brand.

As far as the IAT goes, it's similar in location to K&N's placement with the old FIPK. Can't imagine it's off by more than a few degrees and it's been running with a similar proximity to the air filter since 2000. Geez I've had this thing a long time! Haha!

Thanks for the input fellas! Hopefully this thing will work for the race next weekend. Fingers crossed!

[hobbyturnedobsession]

In regard to what Steve said, when my fuel pump went out, it threw a bad code for the egr valve position sensor... I replaced it like an idiot because I knew what it was... After the fuel pump, the check engine light never comes on.

[Drilim]

I had a maf sensor go out on a road trip in 07. The codes were for something unrelated, but it caused my tranny to shift like I was shackled to a building, no power at all and a horribly rich condition.

I didn't see it noted, but being in Cali your required to run cats? Any chance the element in the cat has broken lose and everything else was incidental and it was do for a tune-up anyway?

[BajaF250]

The MAF sensor didn't pop up on the scanner (in Mexico)....

No sensor is just going to stand up and say "I'm bad! Replace me!"

There is a big misconception that fault codes point directly at the failed part. For example, if you have a code for an Oxygen sensor being out of range, it doesn't necessarily mean the sensor is bad. What it's telling you is that the ECM is seeing a signal that is not within specified parameters. If the sensor is showing a lean condition, either the sensor is bad and won't read rich or there truly is a lean condition and the engine can't compensate for it... indicating a problem somewhere other than the sensor itself.

The mass air flow sensor (again, just an example) could be telling your ECM that the truck is at a completely different altitude than it really is, causing the engine to run an air/fuel mixture that is nowhere near what it really needs.

Buy this book. Unfortunately, it doesn't cover your truck directly, but all the same principles apply and the all the sensors are virtually the same as what your truck uses. Read it front to back and learn all kinds about what it takes to make these systems work.

Right on Steve... Probst writes a great book and it needs to be in everyone's library! It is a book to which I refer to often. I've almost worn my copy out!

[BajaF250]

I believe we swapped the MAP to try at HP Ranch. Brian?

Doesn't have a MAP sensor in '96. I read Ford realized there was no benefit and stopped using it.

Yeah, the MAP isn't used with MAF systems... that's what the hot wire is for... the MAP is used in the speed density system.

B, you hit the nail on the head, the MAF wires need to be cleaned routinely. It may not solve the problem, but it's certainly worth the effort!

I also just went through a bad/broken cat... the symptomes didn't present the same way as yours... but it's easy to check... just drill a hole in the input to the cats and look in... you'll have to weld the hole up, but you have positive proof if the cats are bad (or good).