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Renix power and mpgs problems

so I've done the tips within the past 5 months. i also changed my oil today and that was a nightmare with only one arm. 2.5hours total with all the cleanup involved. double checked the injectors as well in the light and they are 703's. how much of a difference is there with the 703s to 746s? and i also read an 89 edu is better than 88(mine). How come? and is there a difference between manual and auto edu's if i wanted to swap? still haven't been able to check the different sensors.
 
I was more wondering if because i have a manual trans I need to worry about getting an ecu for a manual, or just any ecu from 89 or 90?
 
Long time no progress. Maybe even worse.
So yesterday I had time and disconnected every connector in the engine bay and cleaned and greased and put back together. Same with the ecu. Then I recleaned grounds. Then I tested every sensor right at startup completely cold and when it warmed up. All checks were in accordance to lunghd website. All checked good except the tps was way off(but I already knew that). Tried adjusting right and it was crazy high idle again and the decent idle was a crazy low setting of it. Obviously something is wrong but I can't find anything. Could the tps be bad? It's pretty new. Like a couple months and it's from Napa. I seem to remember seeing a chart of voltages for the tps through a range of Rpms but I couldn't find it yesterday. I wanted to test it through the range of Rpms to make sure it's bad before I spend the money on a new one. Also checked vacuum and fuel pressure and they were both good.

Now the new weird new thing. Vehicle drove the same today but I got a really bad smell of exhaust in the cab while driving. Had to stop and roll down Windows for ventilation. It didn't happen at idle even when I tried revving it at 3 separate stops in parking lots. No smell in the engine bay while idle or revving but when I start driving I get tons of exhaust in the cab again. Just started today and I didn't touch a thing with the exhaust or off-road or anything that would be obvious for letting exhaust out thru loose bolts or holes from hitting rocks or anything. Really weird i can't get a smell at all when I'm stopped only at speed.

Sorry for any misspelled words or bad grammar. I'm rushing thru this on my iPad in between classes.

Thanks for any help.
 
Uncle bob could have manually adjusted (dorked) the throttle body idle stop (bent it with pliers) or idle screw (hidden, not a factory maintenance adjustment) but UB may have screwed with it, making it impossible to get a proper idle speed with a properly set TPS. Or the TPS is bad, or you do not have the TPS installed properly. The Throttle body lever must be on the correct side of the TPS lever. There is substantial TPS test data (ohms and volts) in several posts here listed no where else on the internet and they are in my old RenX Files thread here in the OEM section.

http://www.naxja.net/forum/showthread.php?p=245000672

ljobbins said:
Long time no progress. Maybe even worse.
So yesterday I had time and disconnected every connector in the engine bay and cleaned and greased and put back together. Same with the ecu. Then I recleaned grounds. Then I tested every sensor right at startup completely cold and when it warmed up. All checks were in accordance to lunghd website. All checked good except the tps was way off(but I already knew that). Tried adjusting right and it was crazy high idle again and the decent idle was a crazy low setting of it. Obviously something is wrong but I can't find anything. Could the tps be bad? It's pretty new. Like a couple months and it's from Napa. I seem to remember seeing a chart of voltages for the tps through a range of Rpms but I couldn't find it yesterday. I wanted to test it through the range of Rpms to make sure it's bad before I spend the money on a new one. Also checked vacuum and fuel pressure and they were both good.

Now the new weird new thing. Vehicle drove the same today but I got a really bad smell of exhaust in the cab while driving. Had to stop and roll down Windows for ventilation. It didn't happen at idle even when I tried revving it at 3 separate stops in parking lots. No smell in the engine bay while idle or revving but when I start driving I get tons of exhaust in the cab again. Just started today and I didn't touch a thing with the exhaust or off-road or anything that would be obvious for letting exhaust out thru loose bolts or holes from hitting rocks or anything. Really weird i can't get a smell at all when I'm stopped only at speed.

Sorry for any misspelled words or bad grammar. I'm rushing thru this on my iPad in between classes.

Thanks for any help.
Click to expand...
 
Your new problem may be bad Cat converter or the engine is running too rich and making the manifold or Cat converter glow red hot at cruise speeds. Could you have leaking exhaust valves?
 
Ok, well i got a bored tb from strokedjeep today in the mail and i'm going to install it tomorrow morning then ill go through and readjust the screw and tps and see if anything changes. And as far as the valves go, something may have changed recently but they were all good a few months ago. I had to replace the valve seals around may? and i checked all the springs and rockers and stuff i could check from the top. I did not pull the head so i didn't inspect the valves other than the top. I guess i can check for a sticky valve this week, hopefully tomorrow. Thanks guys.
 
ljobbins said:
Ok, well i got a bored tb from strokedjeep today in the mail and i'm going to install it tomorrow morning then ill go through and readjust the screw and tps and see if anything changes. And as far as the valves go, something may have changed recently but they were all good a few months ago. I had to replace the valve seals around may? and i checked all the springs and rockers and stuff i could check from the top. I did not pull the head so i didn't inspect the valves other than the top. I guess i can check for a sticky valve this week, hopefully tomorrow. Thanks guys.
Click to expand...

Butterfly should be adjusted properly from strokedjeep.
 
ok are you ready? Lots of testing/working today. Long post.

First: I installed a bored tb from stroked jeep. It was not set right. Butterfly valve was completely closed. I started it, idled really rough but when i applied gas it ran ok other than pretty rich and then stalled when i let off the gas. checked the butterfly and it was closed so i opened it slightly to the width of a piece of paper struggling to get thru. it then idled ok and had even better response with gas applied. Ran it for about a week and it runs ok when I'm applying the gas a decent amount but struggles to idle great and hesitates when I'm starting to move, both forward and reverse. Seems like the tps right?

Ok so today i went thru everything according to lunghds website for sensors and other things i could think of. Here are my measurements:
*Ambient air temp outside:approx 75 degrees.
*Coolant temp:195-205
*With the car running: (After cleaning it) Manifold air temp sensor: 725ohms
Coolant temp sensor: 358 ohms
*Car not running(I know it shouldn't make a difference with resistance but i thought maybe with air and coolant moving past it might change things): Manifold air temp:958ohms
Coolant temp sens:308ohms
*Car not running: MAP -5.01 volts to C pin and 4.88 volts to B pin
Car running: MAP 1.44 volts to B pin
*TPS sensor: 4.88 volts and .87 volts. moving the throttle by hand engine off- 1/2 open measured 2.8 volts and wide open measured 4.8 volts
*Vacuum tested 18 in. Jumped from 1-24 with a quick opening of the throttle
*Engine oil good and topped off.
*Every injector firing well with no misfires.
*Every Spark plug firing well with normal engine working condition wear on all of them and correct gap still.
*Set to #1TDC and distributor pointed to trailing edge of #1 on the cap and also had zero build up or wear.
*All wires routed to correct plugs.
*O2 sensor voltage bounced rapidly looking at an analog multimeter and a voltage light.
*Air filter looked pretty clean and it only a couple months old with no real dusty driving during that time.
*Did not check fuel pressure today but i did check it last week and it tested good(can't remember exact numbers)
*Tested EGR and it tested good according to lunghd's site.

Anything i missed? Only thing i wish i had time for was checking all the pins on the ECU to make sure it was receiving all the correct readings and things weren't getting shorted out somewhere between sensors and the ECU. I know the Manifold temp sensor was off but not a crazy amount and I am going to check the junk yard tomorrow morning for a different one. Could the MAT sensor being off that little amount really make that much difference in the idling and throttle response for 1st gear and reverse?
 
Why do you think the MAT readings are off? Keep in mind the MA temp is going to be between the CTS temp reading and ambient air temp, as the ambient air temp has a short residence time in the manifold and the intake manifold is typically about 160 F after warm up (and thus the intake air is about 140 F), while coolant is about 200 F.
 
Same. Any new info?

Sorry to hijack, but my jeep can't get out of its own way on the highway. I nearly have to be in 3rd just to do the speed limit. And significant hill and I'm in 2nd at like 3500-4K rpm to hold 40-45 mph. Jeep has 35's and 4.88's. Auto tranny. 228k miles. Just did a compression test and numbers were good, 125-135 psi. Just recently passed smog with flying colors. Idles fine. EGR working properly. Exhaust is not clogged, no exhaust leaks. Has orange top ford injectors. File pressure regulator is working and psi is correct at idle. Oil pressure is good. No coolant loss. Plugs are good color. Timing chain was replaced a few years ago

Could it just be tired and in need to rebuild? Maybe fuel pump not working when under load?
 
Try a new TPS if it is an automatic, or read my old thread "The RenX Files" on how to run tests and what the test data should show. High probability it is the TPS sensor.

Automatic or manual?

I had 3-4 problems when I bought mine that caused that. Also check the entire vacuum line going to the MAP sensor for even the tiniest sign of vacuum leak.

1990JEEPXJ said:
Same. Any new info?

Sorry to hijack, but my jeep can't get out of its own way on the highway. I nearly have to be in 3rd just to do the speed limit. And significant hill and I'm in 2nd at like 3500-4K rpm to hold 40-45 mph. Jeep has 35's and 4.88's. Auto tranny. 228k miles. Just did a compression test and numbers were good, 125-135 psi. Just recently passed smog with flying colors. Idles fine. EGR working properly. Exhaust is not clogged, no exhaust leaks. Has orange top ford injectors. File pressure regulator is working and psi is correct at idle. Oil pressure is good. No coolant loss. Plugs are good color. Timing chain was replaced a few years ago

Could it just be tired and in need to rebuild? Maybe fuel pump not working when under load?
Click to expand...
 
I didn't think the TPS had that much effect on power. I knew it effected shifting, which is fine. Last time I checked it it was fine. And if the MAP was bad it would run like poo which I would think would show up on a smog test
 
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