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Renix Relay Problem

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Old 08-19-2018, 06:06 AM
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Originally Posted by cruiser54
Not sure if this is correct, but I think 87 relay center may differ from 88 and later because of the fuel pump ballast resistor mod.
Yes, you are correct.
Old 08-19-2018, 08:50 AM
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Originally Posted by ajpulley
Yes, you are correct.

So, what's the order on the 87 without the resistor?
Old 08-25-2018, 10:46 AM
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Short update: Did the sensor ground update - had 1.6 Ohms got it down to 0.7 by soldering the ground wires. But still running rich, choppy und low RPM.

So next was the swap to new 4 hole injectors - still same behaviour - even a little worse. But I've found out that the fuel return line was dripping a little. So could be pressure related.

aMy wife with the new o-rings is on the way - maybe tonight is the night! I will report.

Thanks guys!
Old 08-25-2018, 03:58 PM
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Originally Posted by Dave00
Short update: Did the sensor ground update - had 1.6 Ohms got it down to 0.7 by soldering the ground wires. But still running rich, choppy und low RPM.

So next was the swap to new 4 hole injectors - still same behaviour - even a little worse. But I've found out that the fuel return line was dripping a little. So could be pressure related.

aMy wife with the new o-rings is on the way - maybe tonight is the night! I will report.

Thanks guys!

How is the hose to the MAP sensor and the electrical connector to it?
Old 08-26-2018, 06:54 AM
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Hose is fine, measuring gives out 1.6 Volt during engine idling. Range is 0.5 to 1.5 - is this still okay? I also measured resistance of the cps. Ist says 199 Ohms but just for a short moment, then resistance goes to endless - is this normal?

My engine is running so poor now that have to switch cars for work. What a mess.

Any ideas?
Old 08-26-2018, 07:48 AM
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I test the CPS this way.





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 itself as shown in Figure 2 as Connector A, 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 to 3/8″ from the stock 5/16″, 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.

Another little tip to save tons of aggravation is to stick a bit of electrical tape to your 11mm socket and then shove the bolt in after it. This reduces the chances of dropping that special bolt into the bell housing.
Old 08-26-2018, 07:50 AM
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I wonder if the MAP sensor is bad.

https://www.google.com/search?q=test...hrome&ie=UTF-8
Old 08-26-2018, 12:14 PM
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Yes cruiser you are correct, it’s the MAP! I’ve measured it before injector swap, after swap I’ve forgotten to attach the hose, put it on during engine running. I think I’ve cracked the sensor in that moment. At the moment no voltage on MAP output (exact 5v on input)!

I‘ll order a new one. Thank you so much for standing by.
Old 08-26-2018, 03:54 PM
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Originally Posted by Dave00
Yes cruiser you are correct, it’s the MAP! I’ve measured it before injector swap, after swap I’ve forgotten to attach the hose, put it on during engine running. I think I’ve cracked the sensor in that moment. At the moment no voltage on MAP output (exact 5v on input)!

I‘ll order a new one. Thank you so much for standing by.

You bet. Consider doing this also:

The Renix throttle bodies have a strange and failure prone connector on the side where the MAP supply originates and then runs up to the MAP sensor located on the firewall. This hose/pipe assembly is no longer available for purchase.

The real kicker here is how critical this line is in supplying the correct vacuum signal to the MAP, the most relied upon sensor for the ECU to read regarding air/fuel ratio. Any cracks, melted spots, or loose rubber connectors can cause major starting and driveability issues.

There’s a simple fix though. All that’s required is a 1/8” NPT tap, a new throttle body gasket ( Napa FPG 60742 ), a vacuum fitting (Napa 05703-B102), two vacuum elbows (Napa2-670), and a length of new plastic piping (Napa 2-672).



Remove the throttle body and take it to the workbench.

Using an oiled tap along with a driver, carefully thread the lower of the 2 holes of the throttle body where the old fitting was plugged in. Don’t go too deep. These are pipe threads.

Flush the hole with carb cleaner and inspect for any left over cuttings.
This is an excellent time to do a complete throttle body and IAC cleaning. See Tip 11.
Take the vacuum fitting (05703-B102 ) and apply a LITTLE bit of thread sealer on the threads only. I prefer Permatex #2 but almost anything is fine.

.

Carefully screw the fitting in until snug.

Install one of the vacuum elbows on the MAP sensor so it points toward the throttle body, and the other vacuum elbow on your new throttle body fitting so it points up to the MAP sensor.
Cut a length of the new plastic tubing (approximately 13 inches) to fit between the vacuum elbows and install it making sure there is enough slack for some engine movement. Route it according to the photo. We don’t want any rubbing or chafing with engine movement. Not a bad idea to use some contact cement or Gasga-Cinch sparingly on the tubing to elbow connectors.





Old 10-07-2018, 12:48 PM
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Hey guys, here is my update. After new map sensor and vacuum line IAW cruisers how-to, cleaning the throttle body, putting some bg44 k fuel injector cleaner into the tank, drove 100 km, my rig is doing pretty fine. I call it fixed.

thank you all, another Renix saved!
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