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sluggish take off....?

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My 91 is very sluggish when taking off in drive. and by sluggish i mean you have to give it a lot of throttle, where normally its pretty peppy and just bumping the throttle moves it. feels like maybe as if I'm driving in the "comfort" setting on the comfort /power switch. cuz ive always drove in power but the switch is unplugged now and it doesnt matter if its plugged in. still does the same thing. i had to unplug the transmission control unit to run a new antenna cable and i took the gauge cluster out and put it back in if any of that matters. the TCU was unplugged (forgot to plug it back in) when i started the truck and tried to pull it forward and thats when i noticed it being sluggish. everything is plugged back in how it was and its still barely responsive. once it gets up to speed after taking off it drives fine. just slow to take off. any ideas?

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I would check all your ground wires (side of the block under the sparkplugs there is a stud, and the firewall ground by the TPS) make sure there is no grease or oil. Also check for the CPS... here's a fourm...Renix CPS Testing and Adjusting




Renix CPSs have to put out a strong enough signal to the ECU so that it will provide spark.


Most tests for the CPS suggest checking it for an ohms value. This is unreliable and can cause some wasted time and aggravation in your diagnosis of a no-start issue as the CPS will test good when in fact it is bad.


The problem with the ohms test is you can have the correct amount of resistance through the CPS but it isn’t generating enough voltage to trigger the ECU to provide spark.


Unplug the harness connector from the CPS. Using your voltmeter set on AC volts and probing both wires in the connector going to the CPS, crank the engine over. It won’t start with the CPS disconnected.


You should get a reading of .5 AC volts.


If you are down in the .35 AC volts range or lower on your meter reading, you can have intermittent crank/no-start conditions from your Renix Jeep. Some NEW CPSs (from the big box parts stores) have registered only .2 AC volts while reading the proper resistance!! That’s a definite no-start condition. Best to buy your CPS from Napa or the dealer.


Sometimes on a manual transmission equipped Renix Jeep there is an accumulation of debris on the tip of the CPS. It’s worn off clutch material and since the CPS is a magnet, the metal sticks to the tip of the CPS causing a reduced voltage signal. You MAY get by with cleaning the tip of the CPS off.


A little trick for increasing the output of your CPS is to drill out the upper mounting hole, or slot it so the CPS bracket rests on the bell housing when pushed down. Then, when mounting it, hold the CPS down as close to the flywheel as you can while tightening the bolts.

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Unplug the 3-pin connector from the back of the POWER/COMFORT switch. Make up a short jumper wire jumper using a couple of 1/4" blade connectors on each end, and jumper pins B and C together on the connector. The pins are marked. You are now in the POWER mode. See if that makes a difference.

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