Ford bronco

[Travis]

Hello
I have a 1989 ford bronco that is running rich, it’s in EFI but you can tell the 302 is running richer then it should, and the computer did show a code System rich. The bronco also has a idle surge when the AC is on and it seems to be the worse when you take it out of drive and put it in park With AC off or on.
But it does seems to run ok other then that.
I have replaced the O2 sensor, and have checked the codes in the computer.
The codes were Ignition pickup (PIP) was erratic and EGR did not open/ respond during test or if memory code, did not open intermittently. I tested the EGR by putting a vacuum on it, and it did hold find. Should I still go ahead and get a new one. The check Eng light is coming on for this.

Topic

[Austin]

We need to address one of these concerns at a time. Let’s start with the rich condition. You said a code for system to rich came on. Have you checked vacuum or fuel pressure? First thing I would probably do is put a pressure tester on your fuel rail, KOEO to get the pump to prime and see if it holds pressure, if it drops I would them suspect a leaking fuel injector.

Keep us posted.

[Travis]

I have checked for Vacuum leaks, and did not see any. But the Fuel Pressure I have not. I will do that next. thanks

[EricTheCarGuy]

Yea, let’s not replace any parts till we know they’re bad. The EGR has nothing to do with the idle unless it’s stuck open and that doesn’t happen often. As for the rich condition the first thing to check for is vacuum leaks which you have. You also want to check the operation of the coolant temp sensor as that is what helps tell the computer how much fuel to add. If that’s giving faulty readings it will upset the mixture. More info on solving performance problems like this here.

http://www.ericthecarguy.com/faq/solving-automotive-performance-issues

Good luck and keep us posted on your progress.

[Travis]

Well I finished working on the bronco
the burning rich problem I believe I solved
it seemed to be the O2 sensor was out, and the air temperature sensor had failed
I replaced both of those, and it actually burns quite well
plus it has a lot more power to it. You can feel the gain in power

And I also figured out the EGR valve problem. Which was not the EGR valve itself. I tested it and it held pressure
it was a EGR solenoid. I replaced it, and the check engine light stays off now. I’ll keep on driving it to make sure.

Now my other problem, is the idling problem. Very erratic, you can push on the throttle to even it out.
I did check for vacuum links, using propane.
All seem to check out.

it seems to run pretty good
the erratic idle starts, when you put it in gear
it has to catch itself, and also It seems to be very bad
If the AC compressors Goes off and on

Or when you take it in And out of gear
is a four-speed automatic

That seems To be the only issue now, I was thinking maybe distributor, Or something with in the distributor
or maybe a sensor that I’m not thinking of.
It does come up with a code 14 (Ignition pickup (PIP) was erratic – Ignition Systems)
But the check engine light does not come on.

Thank you

[Stephen Bowen]

PIP code can mean that your TFI module is going south….

But it’s more likely IMO that the pick up in the disty itself either has a bad connection where the TFI hooks to it—or the wiring is starting to give out at the pick up coil itself.

You can pick up a reman disty for the truck with a new TFI module and remove both those possible causes. Yeah it’s a bit of a pain.

I’ve also noted that some models had an ignition control ‘box’ (old school type) If that’s the case? I’d replace the disty, or the pick up coil in the disty. (Let’s be blunt….RockAuto has a replacement disty for a good price, and it’s worth that to save the headache of pulling the gear off that darn shaft…)

I do a lot of work with my Bronco II..which is the baby sister to your larger bronco. The TFI modules if it’s got one? Very suspect to heat fail. Normally if that’s the case–it’ll run worse as it gets warmed up. There are people that do a mod to relocate the TFI module to the firewall on a larger heat sink. Seems to last a lot longer.

The pick up coils/wiring are also prone to failing. And if it craps just right? CAN leave you stranded with a no spark condition.

S-

[angelo paloumbis]

check the fuel pressure regulator may have a bad diaphragm and fuel entering the intake through the vaccum hose

[Author]

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