tayman
NAXJA Forum User
- Location
- Niceville, FL
Okay. did the unplug & start with the O2, MAT and CTS. None affected it. just flared right up and stayed there. about to go get a relay to try the B latch.
Renix Not starting. Fuel pump not priming. only 7v at pump.
- Thread starter tayman
- Start date
Ecomike
NAXJA# 2091
- Location
- MilkyWay Galaxy
If the idle stayed high, then at least part of the problem can not be the B+ relay. If the B+ relay was the problem, and the only problem, the ECU and IAC would corrected the high idle in seconds. Thus your problem is not the B+ system ( or at least not the worst part of it!!!).
I assume the IAC was connected when the O2 was disconnected during the test?
We can not yet rule out problems with the O2 sensor. But try this now, try disconnecting the O2 sensor, then while running disconnect the CTS, then the MAT, then the TPS. Maybe try some in a different order after that. IF disconnected all of those has no effect, I would be inclined to think you have a vacuum leak now, manifold gaskets, throttle body gasket or ???
Don't forget if one disconnecting a sensor drops the idle, immediately check the wires to that sensor for problems, get live data on each sensor wire in the harness, voltage from each wire to the battery ground post!!!!!
I assume the IAC was connected when the O2 was disconnected during the test?
We can not yet rule out problems with the O2 sensor. But try this now, try disconnecting the O2 sensor, then while running disconnect the CTS, then the MAT, then the TPS. Maybe try some in a different order after that. IF disconnected all of those has no effect, I would be inclined to think you have a vacuum leak now, manifold gaskets, throttle body gasket or ???
Don't forget if one disconnecting a sensor drops the idle, immediately check the wires to that sensor for problems, get live data on each sensor wire in the harness, voltage from each wire to the battery ground post!!!!!
Ecomike
NAXJA# 2091
- Location
- MilkyWay Galaxy
I just reread this. Unless the TPS wiring/connectors is sending too high a voltage to the ECU (bad ground, short in the wires....), it sounds more and more like a NEW vacuum leak!!!!!
If you shut off all the air to the top of the throttle body (use a plate, NOT your hand!!!), and it does not die, IT IS A VACUUM leak!!!!!
tayman
NAXJA Forum User
- Location
- Niceville, FL
buddy (with big palms) was able to seal off the intake and kill it.
Ecomike
NAXJA# 2091
- Location
- MilkyWay Galaxy
That is a very bad and dangerous habit to get into, unless you want to loose a friend permanently. A diesel engine will suck the skin off your bones doing the same stunt, and people have died (drowned) that got sucked into/onto pool pump pipe inlets the same diameter.
That bad habit probably starts as kids with a light duty vacuum cleaner.
I forget now where or how I learned not to do that anymore. The pool issue I read about in safety news......
But back to the issue now, based on that test data, It almost sounds like bad data at the ECU???? Like a heavy throttle position being read at the ECU. In other words, time to get after the data testing on the wires while it is running, checking readings at the sensors on the ECU side of the connectors and at the ECU.
tayman
NAXJA Forum User
- Location
- Niceville, FL
Yeah, i know it's dangerous... But anyway,
Are we sure it's mnot a bad Iac motor?
does it make sense that I can cover/uncover/cover/uncover/cover/uncover the IAC port and the motor goes to the closed position? This is what I mean by "tricking" it into closing.
I guess I'll be doing some testing...
Are we sure it's mnot a bad Iac motor?
does it make sense that I can cover/uncover/cover/uncover/cover/uncover the IAC port and the motor goes to the closed position? This is what I mean by "tricking" it into closing.
I guess I'll be doing some testing...
Ecomike
NAXJA# 2091
- Location
- MilkyWay Galaxy
"Yeah, i know it's dangerous... But anyway"
:twak:
The IAC is just a dumb motor. It either works or doesn't. It can stick, and while stuck it is not working even if the ECU tells it to move. But from all your posts, it is obvious the ECU is sending a signal to the IAC to open too much, and then the ECU is not trying to correct the high idle by telling it to close. Did you not say that disconnecting the TPS with all the other sensors connected drops the high idle to normal in a prior post? That would mean the IAC can work when told to close by the ECU!!!!
The only way it could be the IAC is if it is sticking consistently wide open, which I doubt at this point. I thought the IAC was already new, or tried several used ones already? Is it old and dirty? If it is old, have you oiled it after cleaning it? If you have moved the tip forceably on the end you may have damaged it!!!!
:twak:
The IAC is just a dumb motor. It either works or doesn't. It can stick, and while stuck it is not working even if the ECU tells it to move. But from all your posts, it is obvious the ECU is sending a signal to the IAC to open too much, and then the ECU is not trying to correct the high idle by telling it to close. Did you not say that disconnecting the TPS with all the other sensors connected drops the high idle to normal in a prior post? That would mean the IAC can work when told to close by the ECU!!!!
The only way it could be the IAC is if it is sticking consistently wide open, which I doubt at this point. I thought the IAC was already new, or tried several used ones already? Is it old and dirty? If it is old, have you oiled it after cleaning it? If you have moved the tip forceably on the end you may have damaged it!!!!
tayman
NAXJA Forum User
- Location
- Niceville, FL
The mortor is new new. Not a used one. And no, I didn't try to force the pintle to move. I read quite a bit on them before replacing it.
None of the sensors changed anything when un-plugged. I did not try unplugging the tps though. Didn't realize you put it on the list.
What made the RPMs drop before was loosening the TPS bolts and messing with it. back and forth. it would "sometimes" eventually change something enough that the idle came down.
None of the sensors changed anything when un-plugged. I did not try unplugging the tps though. Didn't realize you put it on the list.
What made the RPMs drop before was loosening the TPS bolts and messing with it. back and forth. it would "sometimes" eventually change something enough that the idle came down.
tayman
NAXJA Forum User
- Location
- Niceville, FL
for what it's worth, I told him not to use his hand
:doh:
:doh:
Ecomike
NAXJA# 2091
- Location
- MilkyWay Galaxy
OK, that is where I got the idea the TPS could affect it, which means the IAC was working when it brought the idle down when you worked the TPS. So I am back to thinking wires or grounds or connectors between sensors and the ECU is all that is left.
Unless someone else sees anything we missed????
Time for testing each bloody wire from the sensor to ground and from the sensor to the ECU I think.
The TPS is new right? If not, I would check the TPS idle voltage the next time the idle is too high.
Ecomike
NAXJA# 2091
- Location
- MilkyWay Galaxy
Next time keep a frying pan handy, LOL!
tayman
NAXJA Forum User
- Location
- Niceville, FL
I actually tried using my mudflap, but it was sucking air in still... so he walked over and went "here" *slap*
Anyway, Goodie... MORE FREAKING TESTING!!!! I hate electrical testing.
Ok, so I know how to test ground to battery. that's obvious...
But for sensor to ecu am I just checking resistance to the corresponding pin on the ecu connector? or am I looking for voltage? or??
Ecomike
NAXJA# 2091
- Location
- MilkyWay Galaxy
One goodie, when your done testing electricals on a Renix, you will be a genius with wiring tests, LOL!
You actually have options, but I would make a huge long wire with small alligator clip ends and connect one probe to one alligator clip then the other long wire end to a sensor wire harness wire under the hood. Then probe that same wire at the ECU using the info I sent you (Power OFF during tests). And look for a bad wire, high resistance.
But before you do that you can run the engine, pull the connector on one sensor at a time and check the harness side wires. One should have no voltage (be a ground), and the other should have 4.8-5 volts, on the CTS, MAT. Don't test the IAC, except to verify the ground is a good ground. The O2 sensor has 4 wires, 2 grounds, a 12 volt wire and a 5 volt wire. The MAP has 3 wires IIRC, a ground, and 5 volt wire and return signal wire to the ECU. The MAP, and TPS have 3 wires, 5 volt in, ground, and signal return wire to the ECU. Test the ground and 5 volt supply.
You actually have options, but I would make a huge long wire with small alligator clip ends and connect one probe to one alligator clip then the other long wire end to a sensor wire harness wire under the hood. Then probe that same wire at the ECU using the info I sent you (Power OFF during tests). And look for a bad wire, high resistance.
But before you do that you can run the engine, pull the connector on one sensor at a time and check the harness side wires. One should have no voltage (be a ground), and the other should have 4.8-5 volts, on the CTS, MAT. Don't test the IAC, except to verify the ground is a good ground. The O2 sensor has 4 wires, 2 grounds, a 12 volt wire and a 5 volt wire. The MAP has 3 wires IIRC, a ground, and 5 volt wire and return signal wire to the ECU. The MAP, and TPS have 3 wires, 5 volt in, ground, and signal return wire to the ECU. Test the ground and 5 volt supply.
tayman
NAXJA Forum User
- Location
- Niceville, FL
Well, I know my TPS is good... I've tested and adjusted it so many times that I KNOW it's good.
my O2 only has two wires
I'll do as you said to check the rest
my O2 only has two wires
I'll do as you said to check the rest
Ecomike
NAXJA# 2091
- Location
- MilkyWay Galaxy
Only 2 wires? BINGO!!!!!!! DING, DING, Ding!!!! What happened to the other 2 wires!!!!!
It needs to have the 4 wire sensor!!! The second two wires feed an internal heater that get the O2 sensor hot enough to read right. At idle it does not get or stay hot enough with out the electric heater boost, wires 3 and 4!!!!
Now, since you found the idle stayed high, with the O2 sensor disconnected, I still think the problem is somewhere else, but at some point that O2 sensor being the wrong style will give you idle, stall out, rough idle headaches!
It needs to have the 4 wire sensor!!! The second two wires feed an internal heater that get the O2 sensor hot enough to read right. At idle it does not get or stay hot enough with out the electric heater boost, wires 3 and 4!!!!
Now, since you found the idle stayed high, with the O2 sensor disconnected, I still think the problem is somewhere else, but at some point that O2 sensor being the wrong style will give you idle, stall out, rough idle headaches!
Ecomike
NAXJA# 2091
- Location
- MilkyWay Galaxy
By the way, if you need to drive the beast some, just trick the IAC to a good idle settng, and unplug it for a short road trip here and there.
tayman
NAXJA Forum User
- Location
- Niceville, FL
so why does the harness connector also only have 2 wires? It's the spec sensor for my rig. it's the AX-15 5 speed. I'm guessing different trans, different sensor.
tayman
NAXJA Forum User
- Location
- Niceville, FL
that's what I've been doing...
and I appologize, it's THREE wires. not two.
but still not 4.
tayman
NAXJA Forum User
- Location
- Niceville, FL
Is there anything recommended to clean the O2 sensor? it was pretty black when I pulled it a few days ago.
Ecomike
NAXJA# 2091
- Location
- MilkyWay Galaxy
Only thing I would use is carburetor cleaner or gasoline to clean the O2 sensor.
Wow, old age really sucks, it IS three wires on the Renix Jeeps, sorry, just one common ground, not two.
I have seen too many newer vehicles, not jeeps, in my driveway lately with 4 wires. Not sure now, but the later jeeps may also be 4 wire, hence the confusion.
So I guess you have the right wires and number...
Wow, old age really sucks, it IS three wires on the Renix Jeeps, sorry, just one common ground, not two.
I have seen too many newer vehicles, not jeeps, in my driveway lately with 4 wires. Not sure now, but the later jeeps may also be 4 wire, hence the confusion.
So I guess you have the right wires and number...
