Renix is acting up, could use a hand!

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Jun 22, 2012 | 06:33 PM
  #16  
Quote: How did you adjust the TPS?
I didn't, was slightly confused about an adjustment for it...When installing it, I didn't figure you could twist it without the bolt holes lining up still. Let me run outside and take a look again, hope I don't strip the torx screws, the metal is pretty soft on them.
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Jun 22, 2012 | 06:37 PM
  #17  
Quote: I didn't, was slightly confused about an adjustment for it...When installing it, I didn't figure you could twist it without the bolt holes lining up still. Let me run outside and take a look again, hope I don't strip the torx screws, the metal is pretty soft on them.
Don't run outside without these:


RENIX TPS ADJUSTMENT
Before attempting to adjust your TPS be sure the throttle body has been recently cleaned. It's especially important that the edges of the throttle butterfly are free of any carbon build-up.
IMPORTANT NOTE: With the Key OFF, and using the positive (red) lead of your ohmmeter, probe the B terminal of the flat 3 wire connector of the TPS. The letters are embossed on the connector itself. Touch the black lead of your meter to the negative battery post. Wiggle the wiring harness where it parallels the valve cover and also over near the MAP sensor on the firewall. If you see more than 1 ohm of resistance, or fluctuation in your ohms reading, some modifications to the sensor ground harness will be necessary. The harness repair must be performed before proceeding. I can provide an instruction sheet for that if needed.
MANUAL TRANSMISSION:
RENIX manual transmission equipped XJs have a three-wire TPS mounted on the throttle body. This manual transmission vehicle TPS provides data input to the ECU. The manual transmission TPS has three wires in the connector and they're clearly embossed with the letters A, B, and C. Wire "A" is positive. Wire "B" is ground. Key ON, measure voltage from "A" positive to "B" ground by back-probing the connectors. Note the voltage reading--this is your REFERENCE voltage. Key ON, back-probe the connector at wires "B" and "C". Measure the voltage. This is your OUTPUT voltage. Your OUTPUT voltage needs to be seventeen percent of your REFERENCE voltage. For example: 4.82 volts X .17=.82 volts. Adjust the TPS until you
have achieved this percentage. If you can't achieve the correct output voltage replace the TPS and start over.
AUTOMATIC TRANSMISSION: RENIX automatic transmission equipped XJs have a TPS with two connectors. There is a flat three-wire connector, same as the manual transmission vehicles have, and it is tested the same as the manual transmission equipped vehicles—FOR ENGINE MANAGEMENT RELATED ISSUES.
However, the automatic TPS also has a square four-wire connector clearly embossed with the letters A,B,C, and D. It only uses three wires and provides information to the Transmission Control Module. Key ON, measure voltage between "A" positive and "D" ground. Note the voltage. This is your REFERENCE voltage. Back-probe the connector at wires "B" and "D". Measure the voltage. This is your OUTPUT voltage. Your OUTPUT voltage needs to be eighty-three percent of your REFERENCE voltage. For example 4.8 volts X .83=3.98 volts. Adjust the TPS until you have achieved this percentage. If you can't, replace the TPS and start over. So, if you have an automatic equipped XJ your TPS has two sides--one side feeds the ECU, and the other side feeds the TCU.
FOR AUTOMATIC TRANSMISSION RELATED ISSUES. Check the four-wire connector side of the TPS.
If you have ENGINE issues check the three-wire connector side of the TPS. For those with a MANUAL TRANSMISSION--the TPS for the manual transmission XJs is stupid expensive. You can substitute the automatic transmission TPS which is reasonably priced.
Revised 05-28-2012
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Jun 22, 2012 | 06:57 PM
  #18  
Quote: Fuel filter hasn't been changed since I bought it either.
If I was totally broke I might at least pull the filter, check it out, "back-flush" it. When fuel is low like that it can slosh around a little more and bring crap up.

Cruisers TPS instructions are in the link in my signature. ....
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Jun 22, 2012 | 08:12 PM
  #19  
Quote: Don't run outside without these:


RENIX TPS ADJUSTMENT
Before attempting to adjust your TPS be sure the throttle body has been recently cleaned. It's especially important that the edges of the throttle butterfly are free of any carbon build-up.
IMPORTANT NOTE: With the Key OFF, and using the positive (red) lead of your ohmmeter, probe the B terminal of the flat 3 wire connector of the TPS. The letters are embossed on the connector itself. Touch the black lead of your meter to the negative battery post. Wiggle the wiring harness where it parallels the valve cover and also over near the MAP sensor on the firewall. If you see more than 1 ohm of resistance, or fluctuation in your ohms reading, some modifications to the sensor ground harness will be necessary. The harness repair must be performed before proceeding. I can provide an instruction sheet for that if needed.
MANUAL TRANSMISSION:
RENIX manual transmission equipped XJs have a three-wire TPS mounted on the throttle body. This manual transmission vehicle TPS provides data input to the ECU. The manual transmission TPS has three wires in the connector and they're clearly embossed with the letters A, B, and C. Wire "A" is positive. Wire "B" is ground. Key ON, measure voltage from "A" positive to "B" ground by back-probing the connectors. Note the voltage reading--this is your REFERENCE voltage. Key ON, back-probe the connector at wires "B" and "C". Measure the voltage. This is your OUTPUT voltage. Your OUTPUT voltage needs to be seventeen percent of your REFERENCE voltage. For example: 4.82 volts X .17=.82 volts. Adjust the TPS until you
have achieved this percentage. If you can't achieve the correct output voltage replace the TPS and start over.
AUTOMATIC TRANSMISSION: RENIX automatic transmission equipped XJs have a TPS with two connectors. There is a flat three-wire connector, same as the manual transmission vehicles have, and it is tested the same as the manual transmission equipped vehicles—FOR ENGINE MANAGEMENT RELATED ISSUES.
However, the automatic TPS also has a square four-wire connector clearly embossed with the letters A,B,C, and D. It only uses three wires and provides information to the Transmission Control Module. Key ON, measure voltage between "A" positive and "D" ground. Note the voltage. This is your REFERENCE voltage. Back-probe the connector at wires "B" and "D". Measure the voltage. This is your OUTPUT voltage. Your OUTPUT voltage needs to be eighty-three percent of your REFERENCE voltage. For example 4.8 volts X .83=3.98 volts. Adjust the TPS until you have achieved this percentage. If you can't, replace the TPS and start over. So, if you have an automatic equipped XJ your TPS has two sides--one side feeds the ECU, and the other side feeds the TCU.
FOR AUTOMATIC TRANSMISSION RELATED ISSUES. Check the four-wire connector side of the TPS.
If you have ENGINE issues check the three-wire connector side of the TPS. For those with a MANUAL TRANSMISSION--the TPS for the manual transmission XJs is stupid expensive. You can substitute the automatic transmission TPS which is reasonably priced.
Revised 05-28-2012
turns out, I put the tps on completely wrong. I didn't put the flat spade of it underneath the throttle body lever... . Adjusting it by ear right now, I seem to have gotten it near stock idle points, just doing it to get "close" to normal. Some positions move my idle to 2k+ rpm. I'm a tad confused about the testing procedures, what side of the connector do i test on? engine side? or sensor side? My results are strange. I cannot for the life of me get a steady voltage reading,not even long enough to press hold on my DMM, it jumps around all the time and then goes back to 0.0 after a few seconds. a brief flash of high voltage , my readings were around 3.4~v for reference, .45~ for output, still trying to test as we speak... This is a pita
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Jun 22, 2012 | 08:26 PM
  #20  
one of the fuses in my DMM is blown, no wonder i wasnt getting the right results. have to run to the store now today isnt going well haha
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Jun 22, 2012 | 08:29 PM
  #21  
Use the engine side.
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Jun 23, 2012 | 11:39 PM
  #22  
So, I adjusted the TPS per cruiser's instructions, girlfriend bought me a fuel filter ( good girlfriend ), bought a few feet of vacuum line and replaced some hoses just incase, and now my jeep is running better than it ever has . Thanks a bunch guys for the help, I really appreciate it! I'm originally a motorcycle mechanic, and this forum has made me understand my renix motor like nothing else, don't know what I'd do without it sometimes. Jeep mechanics is a little new to me atm. Thanks again!
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Jun 23, 2012 | 11:50 PM
  #23  
Woohoo. I love happy endings!!!!
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Jun 24, 2012 | 12:11 AM
  #24  
And the crowd cheers! Well done!

Now go back putting things back one at a time, so we know what it was!
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Jun 24, 2012 | 01:34 AM
  #25  
Quote: And the crowd cheers! Well done!

Now go back putting things back one at a time, so we know what it was!
haha, yeah I'm positive it was the TPS, i had it on completely wrong, took a bit to adjust it though. But your post about the fuel filter made me want to replace it just to be safe. Can never be too safe with preventative measures imo
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Jun 24, 2012 | 01:46 AM
  #26  
Just stopped by to say congratulations!
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Jun 24, 2012 | 07:52 AM
  #27  
Quote: haha, yeah I'm positive it was the TPS, i had it on completely wrong, took a bit to adjust it though. But your post about the fuel filter made me want to replace it just to be safe. Can never be too safe with preventative measures imo
Here's a very important free preventative measure for you to do.



Renix Ground Refreshing
The Renix era XJs and MJs were built with an under-engineered grounding system for the engine/transmission electronics. One problem in particular involves the multiple ground connection at the engine dipstick tube stud. A poor ground here can cause a multitude of driveabililty issues, wasted time, and wasted money replacing unnecessary components.
The components grounding at the dipstick tube stud are:
Distributor Sync Sensor, TCU main ground, TCU "Shift Point Logic", Ignition control Module, Injectors, ECU main ground which other engine sensors ground through, Oxygen sensor, Knock Sensor, Cruise Control, and Transmission Sync signal. All extremely important stuff.
The factory was aware of the issues with this ground point and addressed it by suggesting the following:
Remove the nut holding the wire terminals to the stud. Verify that the stud is indeed tightened securely into the block. Scrape any and all paint from the stud’s mounting surface where the wires will attach. Must be clean, shiny and free of any oil, grease, or paint.
Inspect the wire terminals. Check to see that none of the terminals are crimped over wire insulation instead of bare wire. Be sure the crimps are tight. It wouldn’t hurt to re-crimp them just as a matter of course. Sand and polish the wire terminals until clean and shiny on both sides. Reinstall all the wires to the stud and tighten the nut down securely.
While you’re in that general area, locate the battery negative cable which is fastened to the engine block just forward of the dipstick stud. Remove the bolt, scrape the block to bare metal, clean and polish the cable terminal, and reattach securely.
Another area where the grounding system on Renix era Jeeps was lacking is the engine to chassis ground. There is a braided cable from the back of the cylinder head that also attaches to the driver’s side of the firewall. This cable is undersized for it’s intended use and subject to corrosion and poor connections at each end.
First off, remove the cable end from the firewall using a 15mm wrench or socket. Scrape the paint off down to bare metal and clean the wire terminal. Reattach securely.
Remove the other end of the cable from the rear of the head using a 3’4" socket. Clean all the oil, paint and crud from the stud. Clean the wire terminal of the cable and reattach securely.
A suggestion regarding the braided cable:
I prefer to add a #4 Gauge cable from the firewall to a bolt on the rear of the intake manifold, either to a heat shield bolt or fuel rail bolt. A cable about 18" long with a 3/8" lug on each end works great and you can get one at any parts store already made up. Napa has them as part number 781116.
A further improvement to the grounding system can be made using a #4 cable, about 10" long with 3/8" terminals at each end. Attach one end of this cable to the negative battery bolt and the other end under the closest 10mm headed bolt on the radiator support just forward of the battery. Napa part number 781115.
 
 
If you want to upgrade your grounds and battery cables in general, contact Jon at
www.kelleyswip.com. He makes an incredible cable upgrade for a very reasonable price.
 
Revised 11-28-2011
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Jun 24, 2012 | 11:51 PM
  #28  
Never mind I started to post something but didn't the second page of posts.
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Jun 24, 2012 | 11:54 PM
  #29  
Quote: Also just a thought but you might wanna check the fuel pressure. I cant tell you the number of brand new fuel pumps I've had to replace because they didn't put out the correct pressure.
Renixs run at about 40 psi iirc?
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Jun 25, 2012 | 12:08 AM
  #30  
Quote: Renixs run at about 40 psi iirc?
31 with the vacuum line connected to the FPR, 39 with it unplugged.
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