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jrwhite3230

89 comanche losing power and boggs down

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Hello guys I have done  as much as i can do to try and  figure out the problem I'm having my comanche whis is an 1989 jeep pioneer  runs Good  then once  on the interstate starts to like lose power But not  all at opnce it starts  to sputter  Boggs down  then gets worse  and worse can't tell if its backfiring ? but my guesse  it is  !! I have checked  my vacume system but  i need to go over it  again  make sure  everything is  correct ! which i have several times  ! i need  a schematic from someone  who has  made one up on paper if possible  there is  a canister  up front to the right passenger side   behind the front bumper   and just to the  right of  condenser coil !  i don't have  one  But where do those vacume lines Go ? also I have replaced every aspect of  sensors  map sensors Fuel regulator fuel relays  new computer !  I have replaced gas tank  and fuel pump and  filters ! fuel throttle position sensor !  the engine is  rebuilt !   I'm  at a crossroad here But refuse to give in to this ! i need  your help guys i am highly skilled   but this is kicking my Buttocks ! So what ive decided to do is to start  all over  clear  my head and begin at the fuel tank which ive already done ! i pulled the pump out it  checks  fine ! Fuel injectors are good replaced  o rings ! anything Emmisions  I have gone through tooth and nail !    anyways    suggestions  at this  point is much apreaciated !   Thanks

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Does it still have a catalytic converter? A clogged cat will cause low power at highway speeds. 

 

It actually sounds like a fuel delvery problem, could you leave a gauge connected and check fuel pressures at highway speeds? 

 

Good luck!

 

Gene

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Hello guys I have done as much as i can do to try and figure out the problem I'm having my comanche whis is an 1989 jeep pioneer runs Good then once on the interstate starts to like lose power But not all at opnce it starts to sputter Boggs down then gets worse and worse can't tell if its backfiring ? but my guesse it is !! I have checked my vacume system but i need to go over it again make sure everything is correct ! which i have several times ! i need a schematic from someone who has made one up on paper if possible there is a canister up front to the right passenger side behind the front bumper and just to the right of condenser coil ! i don't have one But where do those vacume lines Go ? also I have replaced every aspect of sensors map sensors Fuel regulator fuel relays new computer ! I have replaced gas tank and fuel pump and filters ! fuel throttle position sensor ! the engine is rebuilt ! I'm at a crossroad here But refuse to give in to this ! i need your help guys i am highly skilled but this is kicking my Buttocks ! So what ive decided to do is to start all over clear my head and begin at the fuel tank which ive already done ! i pulled the pump out it checks fine ! Fuel injectors are good replaced o rings ! anything Emmisions I have gone through tooth and nail ! anyways suggestions at this point is much apreaciated ! Thanks

You've came too far to turn back now, I know your frustration JR I deal with it everyday on my job.

You're doing exactly what I have to when faced with an issue like this, step back and clear our head. Man created these monstrosities man will fix!(lol)

Wish you were closer I'd be there to help...G00SE

 

Sent from my LGLS990 using Tapatalk

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Does it still have a catalytic converter? A clogged cat will cause low power at highway speeds. 

 

It actually sounds like a fuel delvery problem, could you leave a gauge connected and check fuel pressures at highway speeds? 

 

Good luck!

 

Gene

 

Does it still have a catalytic converter? A clogged cat will cause low power at highway speeds. 

 

It actually sounds like a fuel delvery problem, could you leave a gauge connected and check fuel pressures at highway speeds? 

 

Good luck!

 

Gene

gene  much apreaciate this  and yeah i did  a fuel pressure check and its all there !  am checking  again and  covering all the  basis !  But I'm about to go advanced because the basics  have  been done this will be  an epic find  because i have covered the field !

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Does it still have a catalytic converter? A clogged cat will cause low power at highway speeds. 

 

It actually sounds like a fuel delvery problem, could you leave a gauge connected and check fuel pressures at highway speeds? 

 

Good luck!

 

Gene

oh and  no the  catalytic converter was  taken off !! its straight exhaust !

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Hello guys I have done as much as i can do to try and figure out the problem I'm having my comanche whis is an 1989 jeep pioneer runs Good then once on the interstate starts to like lose power But not all at opnce it starts to sputter Boggs down then gets worse and worse can't tell if its backfiring ? but my guesse it is !! I have checked my vacume system but i need to go over it again make sure everything is correct ! which i have several times ! i need a schematic from someone who has made one up on paper if possible there is a canister up front to the right passenger side behind the front bumper and just to the right of condenser coil ! i don't have one But where do those vacume lines Go ? also I have replaced every aspect of sensors map sensors Fuel regulator fuel relays new computer ! I have replaced gas tank and fuel pump and filters ! fuel throttle position sensor ! the engine is rebuilt ! I'm at a crossroad here But refuse to give in to this ! i need your help guys i am highly skilled but this is kicking my Buttocks ! So what ive decided to do is to start all over clear my head and begin at the fuel tank which ive already done ! i pulled the pump out it checks fine ! Fuel injectors are good replaced o rings ! anything Emmisions I have gone through tooth and nail ! anyways suggestions at this point is much apreaciated ! Thanks

You've came too far to turn back now, I know your frustration JR I deal with it everyday on my job.

You're doing exactly what I have to when faced with an issue like this, step back and clear our head. Man created these monstrosities man will fix!(lol)

Wish you were closer I'd be there to help...G00SE

 

Sent from my LGLS990 using Tapatalk

Damn you are much apreaciatd  and  yes  i know  you would jump to the occasion to help if  you were  closer  But ill take  what i can get i lived in the  days and  years  of no computer  access  or cell phones   at all communication back then were smoke signals that never  got answered ! food  on the table  meant  ! you better  fix  that there  vehicle  lie or stupid your way into fixing it or  your baby gets no milk at all !   And  that  was how it was  and  ill never  forget the lessons of Ive learned  ! when your  stuck dead  in the desert  and you have no water  but what you have left in your thermos !  what do you do   do you give drnk to  your vehicle in hopes  by devine luck  it gets you home  or  do you savor it and drink one sip per  mile!  on foot ??  well here  i am pondering back in those  days and  days of my father  even more desolet than my own and we  have all this ,mass comunication and  Information comming in from all sources  around the world But yet  here i sit  ! I started out  with no tools back in the  day  and  no way to buy them too  so i made  my own set of wrenches with a  file and hacksaw ! I made every tool imaginable  looking back to  that set of  tools   that now  covers my wall   in a memorial  kind of  way  facing those  tools  there is  a massive set of tools  That only wish  they had what  those hand made tools   had ! I judge  a man by his tool box  whats  in it ? and  are they new   or  used   aren they well taken care of !    that  shows the charactor of a man !  well I hope  i am what i think i am !  

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Hello guys I have done as much as i can do to try and figure out the problem I'm having my comanche whis is an 1989 jeep pioneer runs Good then once on the interstate starts to like lose power But not all at opnce it starts to sputter Boggs down then gets worse and worse can't tell if its backfiring ? but my guesse it is !! I have checked my vacume system but i need to go over it again make sure everything is correct ! which i have several times ! i need a schematic from someone who has made one up on paper if possible there is a canister up front to the right passenger side behind the front bumper and just to the right of condenser coil ! i don't have one But where do those vacume lines Go ? also I have replaced every aspect of sensors map sensors Fuel regulator fuel relays new computer ! I have replaced gas tank and fuel pump and filters ! fuel throttle position sensor ! the engine is rebuilt ! I'm at a crossroad here But refuse to give in to this ! i need your help guys i am highly skilled but this is kicking my Buttocks ! So what ive decided to do is to start all over clear my head and begin at the fuel tank which ive already done ! i pulled the pump out it checks fine ! Fuel injectors are good replaced o rings ! anything Emmisions I have gone through tooth and nail ! anyways suggestions at this point is much apreaciated ! Thanks

You've came too far to turn back now, I know your frustration JR I deal with it everyday on my job.

You're doing exactly what I have to when faced with an issue like this, step back and clear our head. Man created these monstrosities man will fix!(lol)

Wish you were closer I'd be there to help...G00SE

 

Sent from my LGLS990 using Tapatalk

 

Thanks  goose  Ill keep you guys  posted  On  what happens  next   it will be well documented  just in case  anyone else happens to run into what ever the hell it is !! i will get there  ! The  baby is  grown up by now  but still cryin for her babys milk !!  The desert is  beutifull in a comanche !!

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All the vacuum lines on the passenger side use vacuum for HVAC, Cruise and Vac controlled CAD axle. They have almost zero to do with the running of the truck or engine performance. If you don't have a vac reservoir your heater and A/C (if equipped) will just blow out the defrost. Your Cruise (if equipped) won't work properly if at all. If you have a CAD axle, it won't work properly either.

 

The only line you need to worry about affecting the engine would be the large line that comes off the intake manifold and crosses over behind your engine to supply the reservoir with vacuum (the SOURCE line).

 

Does it still have a catalytic converter? A clogged cat will cause low power at highway speeds.

The vacuum on the driver side does affect the engine. But lack of a reservoir will not affect the engine unless that SOURCE line is hanging loose, either not attached to anything or just not plugged and sucking air. Usually it'll cause a higher than normal idle. What you're describing is more attributable to a TPS if you're driving a pre-90 (Renix) rig. The TPS on Renix models is adjustable, and needs to be adjusted. Have you adjusted your throttle valve cable?

 

If it's a fuel delivery problem, it can be lack of vacuum to your fuel pressure regulator...the little round can at the front of your fuel rail...there needs to be a short vac line attached to that too.

 

And then, there's Gene's question. The cat will definitely cause the engine to flat out at a certian load. Like it hits 2500 RPM going up a hill, and you won't be able to get it to rev any further...and it'll drive like crap.

 

Unless I missed it, I don't see any info about your truck. Answering questions is a WHOLE lot easier if we know, the year, the engine etc. Otherwise we're all just guessing.

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Hi  jrwhite3230,

 

We feel your pain!
 
First, please give more history. This is a 1989, is it a 4.0? Still Renix system?
 
You said you're not running a catalytic converter. Any other modifications to exhaust system, or vehicle overall?
 
You state the engine was rebuilt. Was the engine modified in any way during the rebuild? Have the problems been occurring since the rebuilt engine was put in? Were there any problems similar to this prior to the engine rebuild?
 
The Renix system uses lots of sensors, and connector continuity, as well as ground continuity, is essential. If you're not familiar with Cruisers tips, please see and do all of these
 
 
Unfortunately, it seems like many of the aftermarket sensors are total junk. Just because you replace the sensor does not mean that the new one is working well.
 
 
There is lots and lots of wisdom on this board. You providing more information will probably help make this available to you.
 
Good luck!
 
Gene

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It also looks like you were having fuel system problems earlier this year, as you stated in this thread

 


 

How did that turn out?

 

That problem might impact the current problem, if you're not getting adequate fuel delivery you will have problems at higher engine speed.

 

Gene

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All the vacuum lines on the passenger side use vacuum for HVAC, Cruise and Vac controlled CAD axle. They have almost zero to do with the running of the truck or engine performance. If you don't have a vac reservoir your heater and A/C (if equipped) will just blow out the defrost. Your Cruise (if equipped) won't work properly if at all. If you have a CAD axle, it won't work properly either.

 

The only line you need to worry about affecting the engine would be the large line that comes off the intake manifold and crosses over behind your engine to supply the reservoir with vacuum (the SOURCE line).

 

The vacuum on the driver side does affect the engine. But lack of a reservoir will not affect the engine unless that SOURCE line is hanging loose, either not attached to anything or just not plugged and sucking air. Usually it'll cause a higher than normal idle. What you're describing is more attributable to a TPS if you're driving a pre-90 (Renix) rig. The TPS on Renix models is adjustable, and needs to be adjusted. Have you adjusted your throttle valve cable?

 

If it's a fuel delivery problem, it can be lack of vacuum to your fuel pressure regulator...the little round can at the front of your fuel rail...there needs to be a short vac line attached to that too.

 

And then, there's Gene's question. The cat will definitely cause the engine to flat out at a certian load. Like it hits 2500 RPM going up a hill, and you won't be able to get it to rev any further...and it'll drive like crap.

 

Unless I missed it, I don't see any info about your truck. Answering questions is a WHOLE lot easier if we know, the year, the engine etc. Otherwise we're all just guessing.

 

yes  true that  and  thanks  for  replying  this  is  an 1989 jeep comanche  pioneer  rebuilt bored  55 over  basicly equivalent to  boss  302 !  it has no  catalytic converter its been  taken off running straight exhaust !  the canaster you described is missing   also the  a/c is not  connected  or online  yet  so its basicly just for serpenteen belt usage  (a pully at best )  i have no condenser too !  but that vacume line you spoke of comming off the intake manifold is it the one in the rear of  the manifold ? because  its not routed  anywhere and yes  it is sucking a lot of  air !  so if  i don't have  the canaster   should i just plug it ? or  reroute  it to the  fuel regulater  with a  (T) or  just simply plug it ? i am certain this will have an affect to the  problem I'm having !! Also you exsplained about the throttle position sensor (TPS)  its  all new  But I don't believe  i did  anything to  adjust it ! its  at its default  position  But still  should  runn without lossing power ! but I will proceed to adjust this as well leaving no stone  unturned !  I do need  to Revise my  pneumatics (vacume  lines ) make sure  i have them correct  I struggle to find a more advanced  schematic on this  year vehicle  !  youtube is great for many things  But not all !    Thanks  for  your  help !!

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Hi  jrwhite3230,

 

We feel your pain!
 
First, please give more history. This is a 1989, is it a 4.0? Still Renix system?
 
You said you're not running a catalytic converter. Any other modifications to exhaust system, or vehicle overall?
 
You state the engine was rebuilt. Was the engine modified in any way during the rebuild? Have the problems been occurring since the rebuilt engine was put in? Were there any problems similar to this prior to the engine rebuild?
 
The Renix system uses lots of sensors, and connector continuity, as well as ground continuity, is essential. If you're not familiar with Cruisers tips, please see and do all of these
 
 
Unfortunately, it seems like many of the aftermarket sensors are total junk. Just because you replace the sensor does not mean that the new one is working well.
 
 
There is lots and lots of wisdom on this board. You providing more information will probably help make this available to you.
 
Good luck!
 
Gene

 

yes  this  is  a 4.0  6 cyl  bored  55 over  so much larger  cyl  equivalent to boss 302 ! which changes everything  ! the larger  the bore   everything must go up a knotch   and as you said  the defaulted sensors are  designed  for  a  smaller  bore so this could cause  a problem ! Engine machined  at N.a.p.a  !  with the understanding of the  effects of  boring it up they did  the math and three other sources confirmed  the upgrade its should run  with the  supplied equipment that was original to the vehicle ! but with more Horse power ! 

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Yes, plug that line OR put a plug/cap on the intake manifold itself and delete the line until you have a need for it. FYI, the lack of vacuum on the passenger side will make you HEATER blow through the defrost vents only...by default, so it's not just the A/C. The line(s) coming out of the firewall next to the heater fan housing operate your heater vent/blend doors and they run off that vacuum (pink or light colored one is for the heater valve, black one operates the blend doors). If all that stuff is ripped out, or you don't care if it blow thru defrost only, plug them all and come back to them.

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Did this engine ever run well since the rebuild?

 

Did it run well prior to the rebuild?

 

And what was wrong with the fuel system earlier this year?

 

Gene

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Yes, plug that line OR put a plug/cap on the intake manifold itself and delete the line until you have a need for it. FYI, the lack of vacuum on the passenger side will make you HEATER blow through the defrost vents only...by default, so it's not just the A/C. The line(s) coming out of the firewall next to the heater fan housing operate your heater vent/blend doors and they run off that vacuum (pink or light colored one is for the heater valve, black one operates the blend doors). If all that stuff is ripped out, or you don't care if it blow thru defrost only, plug them all and come back to them.

Hi paradise  thanks man  for  the  reply  forgive me for  replying back late Ive been full bore on this  truck !! at the moment i got the truck running  what i did  was  take that rear intake  vacume line and  T'd it  to the fuel regulater so far  the truck is running but still drops out boggs down when i press on the gas ! Which tells me  i need  to adjust  the  T.P.S which is  new But!! the one  i purchased  was  a two wire T.P.S for  an automatic which i have  a manual transmition ! so I'm trying to find out if  there  is  a discrepencey between the two ? I paid about  $50.00 bucks for  the automatic T.P.S  went back to see  what the  manual one cost it was  $130.00 bucks  which in case  i will try and locate one from  U-pull it here in tampa !  eighther way I'm  trying to see if  it matters  between the two !  ?   also  My a/c isnt online i have it disconnected  and I don't have  a condencer  or  the vacume canaster in the front  [assenger  side next to radiater  ill be locating one  in a couple days  and  have all that  back online then ill replace  that one vacume line back to its  defaulted  position in the canaster !     so  thats  where I'm at  i  will be  posting pics  of wiring that i do not know what or  where  they go to ? soon as i can figure out how to get the pics  into  this  post ! Thanks   again

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Does a two wire (connector)  automatic transmition T.P.S  also work with  a  manual Transmition , Which originaly used  a single wired connector for  a  1989 jeep comanche pioneer ?

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Yes.   I had a 5 speed that already had a two connector TPS, when I swapped the AW4 into it, I kept the TPS and still working fine.  Look on cruiser54's site to test and adjust your TPS, you'll need a volt meter.  Be careful of the small screws on the TPS, they're small...and loseable.  You needn't remove them to adjust, just loosen.

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Yes.   I had a 5 speed that already had a two connector TPS, when I swapped the AW4 into it, I kept the TPS and still working fine.  Look on cruiser54's site to test and adjust your TPS, you'll need a volt meter.  Be careful of the small screws on the TPS, they're small...and loseable.  You needn't remove them to adjust, just loosen.

Thanks paradise that was  a $130.00 question I went to O-Rileys and asked for a manual T.P.S they quoted me  that price !!  YIKES was my Thoughts !  Now its  all about Re-adjusting the T.P.S heading over to cruisers Renix on that  thanks !!   can't wait to get the  mechanics  right so I can start on cosmetics !! Ill be  posting  before  and after pics  and keep it all well documented !

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what were the readings after testing the TPS?  what about the MAP sensor?  

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17 hours ago, jrwhite3230 said:

This  is  a jeep comanche  pioneer !989  !

 

89 comanche 4.0 6cyl Bored 50 over.JPG

Your grill is upside down- BTW

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