So i bought a 51 Whilly

zukkev · Jan 20, 2011

Hip, have you tried unplugging the EGR to see if that changes anything???
And yours is a 93 motor? Does it have the IMTV (intake manifold tuning valve) on top of the plenum? If so, is it stuck/ in wrong position at idle???

ain'tstuckjustresting · Jan 20, 2011

Yes Kev, all the CPI's have the tuning valve but I'm not sure it could cause this symptom.

zukkev · Jan 20, 2011

Yeah I know, but I have seen some that have changed to the later intake setup thinking it would simplify everything, and have had more issues than before! (wonder why!:redneck

ain'tstuckjustresting · Jan 20, 2011

I know right! I started looking into the conversion to a 96' injection system but I figured I would spend a **** ton of money then still have the same problem.

Hip · Jan 20, 2011

ain'tstuckjustresting said:
Hip, your symptoms are the same as mine, same motor, almost same codes. FWIW I installed brand new ac's in mine before I installed it so I doubt that's your problem.

Your thread got me thinking though. I have a 92-93 motor and the prom and harness I got from howell is for a 94-95. I know the egr's are different I'm wondering if anything else is? I had to switch my egr plug around to make it work.

What brand spider did you install? Mine's a BWD and the regulator is set too low. I'm on my 2nd one with no change. I installed an external regulator for testing purposes just to get up around 60-62psi.

my egr is not on line the harness eliminated it. i cleaned up the tuning valve when doing the CPI spider.

the CPI is a reman from fuel injectors.com second one ive used from them. i repaired a friends car that had issues it took me a week to figure out.

im pretty sure mine is something that is intermittently working not working....sometimes it runs smooth then starts to run rough.

although im wondering if it might be my ECU as most of the codes it showed were for low voltage at the map, iac, tps i dought all of the ones i have are bad. the one thing they all have in common is the ecu.

well since im 800 dollars short of driving it i guess i got time to figure it out?:booo:

Binder · Jan 20, 2011

Hip said:
im pretty sure mine is something that is intermittently working not working....sometimes it runs smooth then starts to run rough.

although im wondering if it might be my ECU as most of the codes it showed were for low voltage at the map, iac, tps i dought all of the ones i have are bad. the one thing they all have in common is the ecu.

Very unlikely it's the PCM. Sounds like you have a low voltage issue.....1 wire alt? Issues are at idle?

Hip · Jan 20, 2011

yes it appears to be setting its self up to lope at idle.

three wire alternater and its putting out voltage just fine now that i hooked up the exciter wire.

doesnt the ECU produce control voltage?

i did check the voltage to the IAC and it was less tha 1 volt and should be 4.5 to 6V.

saturday i have a friend who has the same stock motor and they will bring their vehicle over and let me swap some stuff out till i find the culprit. if that fails i will be talking to the company who made my harness and ECU prom.

TreeClimber · Jan 20, 2011

After it runs for a while, and you shut it off, do you have a hard time restarting it? Or does it fire off easily.

Hip · Jan 20, 2011

TreeClimber said:
After it runs for a while, and you shut it off, do you have a hard time restarting it? Or does it fire off easily.

fires right up although i do have to open the accelerator a little and should not have to at all...runs smooth for about 30 seconds to a minute then starts loping, once the loping starts runs crappy.

the loping seems to me to be vacuum related but i do not have a gauge to measure what is happening to vacuum. i will have some way by saturday to verify vacuum pressure while operating.

TreeClimber · Jan 20, 2011

Try replacing the temp sender.

Strictly a guessing game. But it's my guess (for now). My guess scenario goes like this. Engine temp sender is too cold, so engine fuel map is sending too much fuel, trying to 'cold start', as the engine warms up, the fuel map keeps trying to compensate for the cold run, but ends up too rich in the exhaust, so it keeps cycling back & forth trying to wam up without running too rich. And since it's too cold, it cannot go to closed loop.

T

zukkev · Jan 20, 2011

Hip said:
although im wondering if it might be my ECU as most of the codes it showed were for low voltage at the map, iac, tps i dought all of the ones i have are bad. the one thing they all have in common is the ecu.
well since im 800 dollars short of driving it i guess i got time to figure it out?:booo:

And the wiring between it and the motor...:;

Hip · Jan 20, 2011

TreeClimber said:
Try replacing the temp sender.

Strictly a guessing game. But it's my guess (for now). My guess scenario goes like this. Engine temp sender is too cold, so engine fuel map is sending too much fuel, trying to 'cold start', as the engine warms up, the fuel map keeps trying to compensate for the cold run, but ends up too rich in the exhaust, so it keeps cycling back & forth trying to wam up without running too rich. And since it's too cold, it cannot go to closed loop.

T

food for thought i do have another one to try.:awesomework:

zukkev said:
And the wiring between it and the motor...:;

yeah thats why i paid for a brand new harness and matching ECU. if i cant figure this out or i at least eliminate all the sensors then ill be on the phone with them. they have been very helpful over the phone....

Binder · Jan 20, 2011

Hip said:
doesnt the ECU produce control voltage?.

It steps down the system voltage from 12ish to about 5 volts but if the input voltage is inconsistant the output can be too. Some things still need 12 volts too...Injectors...O2 sensor heater.....
It now sounds to me like it's acting up when it goes into closed loop. What you destribe as a "lope" is what I think most people call a "surge". Bunch of things can cause it and some of them aren't easy to fix....If it were mine I would run it open loop and see if it still does it. Just unplug the O2 sensors. May only have to unplug one, I'm not sure...Mike?
Has the throttle body adjustments been messed with?

crash2 · Jan 20, 2011

Binder said:
It steps down the system voltage from 12ish to about 5 volts but if the input voltage is inconsistant the output can be too. Some things still need 12 volts too...Injectors...O2 sensor heater.....
It now sounds to me like it's acting up when it goes into closed loop. What you destribe as a "lope" is what I think most people call a "surge". Bunch of things can cause it and some of them aren't easy to fix....If it were mine I would run it open loop and see if it still does it. Just unplug the O2 sensors. May only have to unplug one, I'm not sure...Mike?
Has the throttle body adjustments been messed with?

As rick stated it drops the voltage to 5volts. You won't see that voltage drop below 5 even if the system voltage is down to around 9 but by that time the ecu will start to shut down but the 5v will stay constant.

I will sit down and read more into this when I have a chance tonight hip and give ya my .02

ain'tstuckjustresting · Jan 21, 2011

I know mine will stop the idle surge after you drive it a bit but it still runs super rich. Sounds as though I'm getting spark knock under load too. I never noticed it until I got it on the trail.

Edit: Mine also had the problem before I installed my O2 sensor.

Hip · Jan 21, 2011

thanks for all the comments and help it is frustrating.

i appreciate this as im not the best EFI person around....:redneck:

Hip · Jan 23, 2011

ok so i figured out how to adjust the voltage to the throttle position senser, you have to turn the idle set screw after removing the little tamper cap. so it was set at .233 and is supposed to be between .465 and .615 V, now is constant at .485V

turn engine off for at least 15 seconds.

Start engine and ensure correct idle speed.

Went perfect for thirty seconds then starts to lope :eeek:

i did find a missing vacuum plug thats now pluged. it was there but was loose.

fawker runs actually pretty darn good except for the lope.

Rick just for you i tried to disconnect the O2 senser and it runs but definately not better and after a few minutes wont stay running. connect it back up and works much better.

it seems like when the ecu takes over after start up (30 seconds) it starts the lope.:looser:

Binder · Jan 23, 2011

Hip said:
ok so i figured out how to adjust the voltage to the throttle position senser, you have to turn the idle set screw after removing the little tamper cap. so it was set at .233 and is supposed to be between .465 and .615 V, now is constant at .485V

turn engine off for at least 15 seconds.

Start engine and ensure correct idle speed.

Went perfect for thirty seconds then starts to lope :eeek:

i did find a missing vacuum plug thats now pluged. it was there but was loose.

fawker runs actually pretty darn good except for the lope.

Rick just for you i tried to disconnect the O2 senser and it runs but definately not better and after a few minutes wont stay running. connect it back up and works much better.

it seems like when the ecu takes over after start up (30 seconds) it starts the lope.:looser:

Even though the volage will change that's not how you adjust the TPS volage. What you adjusted is the IAC. You now need to adjust the IAC back to spec then adjust the TPS. Some TPS' arent adjustable but there's ways to cheat on them.........If it were mine I would use the .223 voltage as a reference to get the adjustment back where it was. Make sure you're testing the TPS voltage on the correct two wires (I would have to look it up) then you can adjust the TPS voltage by very slightly bending the metal tab where the TPS butts up againts the throttle body linkage....
Have you checked fuel pressure with a gage?

Binder · Jan 23, 2011

Before you get too far into it you may want to see if the TPS is working correctly. With the volt meter hooked up work the throttle by hand (key on engine off) slowly and watch the voltage. It should move steadily in progression without any jumps up or down. You're looking for dead spots where the voltage has a dead spot or spike....Could be bad at idle.

ain'tstuckjustresting · Jan 23, 2011

Hell I was just going to bump this thread since I have mine in the shop right now too.

Throttle Position (TP) Sensor

ADJUSTMENT & TESTING

The TP sensor wiring should consist of a 3-wire harness connector. The gray wire is normally the 5 volt reference signal from the computer control module. The dark blue wire should be the TP signal and the black wire is ground.
Because the TP sensor on these engines is bolted into a fixed position, no adjustment is necessary or possible. If the sensor does not give proper readings (and other problems with the circuit are not to blame), the faulty TP sensor must be replaced.

If available, connect a scan tool to the ALDL/DLC. If a scan tool is not available, use a digital voltmeter to backprobe the TP sensor connector terminals for the ground (black wire on end of connector) and sensor signal (dark blue wire usually at center of connector). By backprobing the connector, a voltage reading can be taken without disconnecting the circuit and without piercing the wires.
Turn the ignition ON, but do not start the engine. Check the voltmeter or scan tool for TP sensor output. Voltage should be 1.25 volts or less with the throttle closed. Open the throttle and watch for a smooth change as the voltage increases. Voltage may go as high as 4.5 volts at wide open throttle. If voltage with the throttle closed is greater than 1.25 volts, or if the voltage does not increase smoothly as the throttle is opened, replace the sensor.