95xj 4.0 TPS sensor volts .08 to 3.8 is good right? Plus 02 goes lean/rich/lean/rich

Just got a scanner and code reader and was just checking all my sensors how can i check that all my sensor readings are good???

-tps is .08 to 3.8 volts at WOT
-02 sensor never stays the same it runs from lean to rich as i drive and never stays in one place
-map sensor is 1.5 at idle and sticks pretty low which means i have pretty good vacuum prob becuase all vacuum lines and fuel vapor canister is removed.
-coolant sensor seems to match degree's of coolant temp so thats good.

Anything else I need to check and make sure is good.

I got this because i was getting a injector code but it was getting heat soak from header and going into vapor lock # 3 injector, now its fine since it has radiant barrier on it.

any help thanks guys

FSM will have all the sensor specs. O2 toggling is normal, they switch rich/ lean and the fuel trims go with.

I'm away from home and don't have my 95 FSM handy, but as far as I know, the 95 OBD system does not detect any non-electrical issues such as vapor lock, fuel starvation, leaky injectors and so on, and I don't think the detection of general misfiring comes in until 96 (and that's a different code anyway), so if you were getting an injector code, I'm pretty sure you're looking at an electrical fault either in the harness or the injector.

Heat soak could still be causing the fault to appear. I've seen that problem with bad splices in the wiring harness. It might be a good idea to do some further sleuthing on the injector circuits. In the case I had, an injector tester passed the harness, but when hot a bad splice cut voltage just enough to stop one of the injectors. It ran fine cold, but dropped to about 8 volts hot, enough to stop firing. Hard to track down since it occurred only while driving, and not every time. An ohmmeter caught it.

If the misfire occurs again, you can isolate it quickly, by unplugging the injectores one at a time while idling. When you unplug a good injector, the engine will bog a little, then recover. When you unplug a bad one, nothing changes. Zap the throttle a bit between pulls to keep the engine from loading up. You can isolate the problem further by swapping the connector from the bad injector with its nearest neighbor. Repeat the test. If the fault follows the connector, it's the harness. If it stays on the injector, it's the injector.

Yea i havent gotten that code27 since i swapped the 3rd injector to 1st injector so not sure. as far as sensors and specs where do i find the 95xj fsm's??

95cherjustin said:

Yea i havent gotten that code27 since i swapped the 3rd injector to 1st injector so not sure. as far as sensors and specs where do i find the 95xj fsm's??

Click to expand...

I don't know where you can get the manuals now, maybe ebay or something. If you need specs for sensors, I can probably find them in mine, but I won't have access for a couple of days.

okay cool i guess let me know if you find something on specs

I am home briefly in between emergencies of one sort or another, and have found half of my 95 FSM. It got torn apart in a freak accident in which a truck crashed through my shop. As I write, I now recall that the electrical half is inside the 95 where I was troubleshooting the wiring harness. Anyway, I have here some sensor test values.

Coolant temp and manifold air temp sensors have same values, and are read in ohms resistance. There's a long chart, but a few values are probably enough to give you an idea if they're working:

50 degrees F = 17990-21810 ohms
68 degrees F = 11370 to 13610
77 degrees F = 9120 to 8750
104 degrees f = 4900 to 5750
158 degrees F = 1630 to 1870
212 degrees f = 640 to 720

Map sensor : test output voltage at connector between terminals A and B as marked on the sensor body. Ignition on, engine off, output voltage should be 4 to 5 volts. It should drop down to 1.5 to 2.1 at neutral hot idle. PCM Terminal 5 should have the same voltage if harness is good. Test supply voltage at terminals A and C, ignition on, engine off. It should be ~5 volts, plus or minus .5, as should terminal 6 of the PCM. Ground is terminal A. You should get continuity between PCM terminals 4 and 11, if not check sensor ground.

Crank position sensor - other half, will look later.

TPS: Center terminal is output. With key on, back probe, and check voltage at idle position and Wide open throttle. At idle, should be greater than 200 millivolts. At WOT, must be less than 4.8 volts. Should increase gradually without glitches when throttle is opened.

O2 sensor heating element (white wires) should read 5 to 7 ohms. Replace if it reads open circuit.

That's most of it. Basically the crank and cam position sensors will either work or not, so there's not much to be gained from getting readings.

If more is required in some specific area, let me know and I can look further, and hunt down the electrical section.

95cherjustin said:

Yea i havent gotten that code27 since i swapped the 3rd injector to 1st injector so not sure. as far as sensors and specs where do i find the 95xj fsm's??

Click to expand...

Here: http://www.autobooksbishko.com/search.cgi?year=1995&make=Jeep&category=Shop+Manual

This company has LICENSED reprints and CDs.