Thanks guys! Ill get to checking all the sensors in that link with the voltmeter. Finaly found a use for the thing lol I def have plenty to do know. I wont be able to get starter until friday morning but ill update you guys with my progress.

I did get the CPS from one of the big box stores, Autozone. So i guess its possible its a cheapo?

And 5-90 I am in the metropolis of Neosho, MO deep in the heart of the Ozarks, AKA Gods Country

 

That's what I read as well ^^, then Cruiser told me it was 70%. (If I recall correctly) Since he was coming down a mountain, reading from a stone tablet, I'm not going to disagree!

(academic in any case)

Yea, OP, just too easy to rule out the CPS and put that one to bed. Easy for me to say since the little alligator clips I soldered on my leads clip neatly in/on the connector. I thought mine was getting by OK at .3V. It soon dropped from there, then with the new Echlin from Napa, it starts better and runs smoother at .56V.

 

Too funny!! Flintstone, you're right. Too many marginal CPSs out there, used and new!!!!

 

Erm, not so much.

MAP and IAT signals are used to meter air as it enters the engine (temperature/density system,) and therefore generate the basis for fuel metering - not feedback.

The only sensor on RENIX (or pretty much any other engine) that generates a feedback signal is the HEGO - because "feedback," by definition, is a signal generated to monitor the process after it has occurred.) Since the MAP signal technically is used as a primary input for fuel metering, it can't provide a "feedback" signal.

Apart from that, I think you're on the right track.

OP, you'll be able to do most of your testing with a decent DMM (Digital Multi-Meter,) there are only a couple of sensor tests that will require an analogue, and you're not likely to run into them with this. As far as location, perhaps there's someone who can drop by and help you? I haven't been to the Ozarks in a long time (but I should probably correct that sooner or later. Grew up in Indiana, so I've been around there...)

 

Thanks 5-90. I'm learning here and it's always nice to hear your input. OP, I Googled "HELO", it's the O2 sensor, and Cruiser, it doesn't supply info on cam position.

 

Smartalec.

 

"HEGO", not "HELO." "Heated Exhaust Gas Oxygen sensor."

The earliest ones lacked a heating element, and were therefore called "EGO" (Exhaust Gas Oxygen sensor.)

The HEGO can be further divided into two class - NHEGO (Narrowband Heated Exhaust Gas Oxygen sensor) and WHEGO (Wideband Heated Exhaust Gas Oxygen sensor.) The NHEGO is the one typically used in OEM applications, and only really shows useful response over a narrow range of AFR. The WHEGO has a much wider operating range (from below LBL to above RBL,) and is the type generally used in the aftermarket AFR monitors, like the one by Innovate Motorsports.

OEM NHEGO sensors can also be divided by the type of ceramic used to make the air battery - either Titania or Zirconia. I'm not firm on just which is which, but one type is a true "air battery" and generates a voltage output of 0 to +1VDC (with stoich being +0.5VDC); and the other presents as a variable resistor, and gets used as a divider for a reference voltage signal (typically +5VDC.)

RENIX uses the latter type, which is why they'll mechanically swap but the output signal will be nonsense (causing the ECU to fail into open loop mode, and run rich.) The variable resistance type is uncommon, the voltage output sensors are in much wider use.

(LBL - Lean Burn Limit, which is the point at which there is not enough gasoline vapour to support combustion. For gasoline, this runs about 8:1 or so.)

(RBL - Rich Burn Limit. At this point, there is too much fuel to support combustion, and the system rapidly depletes its oxygen. I believe this is up around 19:1 or so, for gasoline.)

 

Sounds like fuel pump, regulator or transfer hose between fuel pump pick up tube and pump housing[the 3inch long soft line] is loose. All 3 of those made my renix run like crap a backfire through the t.b. under acceleration. Just my past experience.

 

Well I rented a fuel presure tester for autozone and the fuel presure is at about 25!!! It did not make a difference when i hooked or unhooked the vacuum hose from the fuel presure regulator. I am not real sure why it would do that does this mean the regulator is bad or what is this case?

 

Good to know.

 

is there anything else i need to check? kinda wana get this pos figured out today going out of town for a few days.

 

Can he pinch off the return line and see if the pressure goes up past 39 psi. ? Then if so suspect the regulator, and if not suspect the pump?

And OP, with out re-reading...did you verify you have that you have 9-10 , or 12 Volts (if it's bypassed), to the wire to the pump out of the rear of the ceramic ballast resistor on the inner fender, near the air cleaner?

 

Pull the hose off the FPR and see if there's gas in it. I suspect your fuel pump is taking a dump.

 

Well after my last post i read more in my Haynes manual and checked the FPR by pinching off the hose with visegrips. The FPR seemed fine so checked all the lines and discovered a hose clamp missing from where the line goes on to the fuel pump. Fixed that and it didnt change anything so I just purchased a new fuel pump that Ill install next week.

I also did the ground wire refresh as per a post I found on this forums. That seemed to make it run a bit better and the headlights seem brighter.

Appearently the complicated volt meter I have is beyond my mechanical abilitys as I could not figure out how to get it to work even with the detialed instructions from the link that was posted. So I just got a new O2 sensor because the old one look like it could have been the original lol. It does run a lot smother with the new O2 sensor but still idles rough, boggs down and backfires a little. The backfire is ALOT less tho.

I greatly appricaite the help and will post results when I install the new pump but it'll be a few days. I have a feeling this Jeep will be like my old project motorcycle...I great learning experence.

PS please excuse my bad spelling errors as I didnt have time for spell check, leaving for a weekend get away with the wife and in a hurry.

 

Ground refreshing makes a real difference. Good idea on the O2 sensor. Have you tested your TPS with your new meter? Good way to learn. Remenber this: Myself and many others were dumbfounded by those dang meters at one point in our lives.