Reduce power light


KLJ
01-07-2005, 11:46 AM
Reduce power light and check engine light comes on then I can push gas pedal and I am lucky if I can go 10 mi. any one know what it might be replaced o2 sensor and throttle postion sensor because it threw out those codes but still does it .

Canucklehead
01-07-2005, 12:00 PM
Reduce power light and check engine light comes on then I can push gas pedal and I am lucky if I can go 10 mi. any one know what it might be replaced o2 sensor and throttle postion sensor because it threw out those codes but still does it .

First off, what year is your vehicle?
Second, you are lucky if you can go 10 mi. and what...?

If your lights dim it could be your alternator is on its last legs, but without more info it's hard to roubleshoot your problem.

amigo-2k
01-07-2005, 12:10 PM
He has a 2001 Rodeo (in his profile; thanks for filling it out!)
My best guess is this:
3. Check The Ground At The Alternator Bracket

Here is a link to some other idea's (I'm pretty sure this is an electical issue):

http://www.geocities.com/endre_rl/isuzufaq.htm#faq61

here is a link to someone who had the same thing happen:

http://forum.planetisuzoo.com/viewtopic.php?t=2867&;

2eyefishclaw
01-07-2005, 05:20 PM
definatly broken wires in harness

KLJ
01-08-2005, 01:59 PM
sorry its a 2001 Isuzu Rodeo, the reduce power light comes on then the check engine light then it slow down to a crawl even with the gas pedal all the way to the floor. But it doesnt quit running . Thanks

rodeo02
01-09-2005, 03:15 PM
Could this also be a failed throttle by wire component? IIRC, someone on planetisuzu had similar symptoms & that's what it was, bad TBW.

G/luck
Joel

KLJ
01-10-2005, 12:19 PM
Thanks Joel I will look into that . Do you know how to check the wires?

amigo-2k
01-10-2005, 12:40 PM
Could this also be a failed throttle by wire component? IIRC, someone on planetisuzu had similar symptoms & that's what it was, bad TBW.

G/luck
Joel


if someone finds this recent post; post it here.

427hvn
01-10-2005, 08:23 PM
Let Me Know What You Find Out If You Fix The Problem Mine Has Been Doing The Same Thing For About 2 Months Does Yours Surge Down The Road? I Have Been Checking Wires And Ground For A While But No Luck Yet I Have A 01 With V6

KLJ
01-11-2005, 12:27 PM
Yes, sometimes it does do that also it just started when I am braking sometimes really hard it just dies. But I am still trying to find the reduce power light problem checking the wires around the throttle. A guy on another site said it might be an idle speed control actuator he said it cost around 300 bucks just for the part I hope not.

427hvn
01-11-2005, 05:50 PM
I Had The Codes Read It Came Up With Like 6 Different Ones That Pretained To The Egr And Throttle Position Sensor I Replace Egr First At Around $100 Not The Problem I Replace The Tps At Like $150.00 No The Problem I Took It To A Mechanic That "guaranteed Diagnosis" $188.81 Later He Says It Is The Tps That I Had Replaced 2 Days Earlier He Said I Have 30 Years In The Business I Know What I Am Talking About. So I Ordered A New Tps At Another $150.00 Guess What I Wasn't The Problem Old One Was Sent Back For Testing And It Was Good! Mine Dies When I Park Alot The Reduced Power Light Comes On Usual When I Make Turns But Sometimes Just For The Heck Of It. I Am Not Sure If The Idle Sensor And Throttle Sensor Are The Same Thing But That Wasn't The Problem With Mine. I Have Been Talking To A Guy On This Site That Is An Isuzu Tech He Said These Years With This Motor Have Had A Lot Of Wiring Related Problems And We Are In The Process Of Going Through Them Now So Far With No Luck. Good Luck And Keep Me Updated Maybe We Have The Same Problem

KLJ
01-11-2005, 07:28 PM
Throttle postion sensor and the idle speed control actuator sensor arent the same . But I dont know where to start we have went thru some wires. Its just expensive and time consuming . Let me know about yours too maybe we will figure it out.

rodeo02
01-12-2005, 06:23 AM
if someone finds this recent post; post it here.

Here's that TBW post I was thinking of. Look towards the end of the thread. http://www.forum.planetisuzoo.com/viewtopic.php?t=2775&highlight=dbw
G/luck!
Joel

KLJ
01-14-2005, 05:48 PM
Thanks Joel sounds like my problem .

KLJ
01-24-2005, 05:15 PM
Hello Guys Isuzu dead on the side of the road with the problem it was still having after tons of searching new techincan says it is the motor on the throttle body , 525 for the part and 150 for labor , 50 for tow. Hope this helps somebody with the same trouble.

2eyefishclaw
01-24-2005, 09:06 PM
alright guys here it is I repair one or more of these a week first few I had I also thought it was the tbody but one of them got me on day normally when replacing the t-body the engine harness gets moved around which can make it seem as though the vehicle has been repaired but it usually comes back to bite you in the backside
best suggestion remove the 10mm bolt that holds the engine harness down to the drivers side valve cover run the vehicle for about twenty minutes or untill the harness is nice and warm for once its warm its going to move easier
ok now that is warm pop the hood leave it running grab the harness near the hold down bracket where you removed the bolt pull twis and tug on that darn thing as hard as you can if the vehicle stumbles or dies out guess what its time to go swimming in the harness thats where it gets fun remove the wire loom as much as you can get to pull on each wire one at a time remember you are trying to get one of them to break but dont be a gorilla give the a good tug you may find one or more of the wires will break just solder them back together and you will be good to go

KLJ
03-21-2005, 09:22 AM
Throttle postion sensor and the idle speed control actuator sensor arent the same . But I dont know where to start we have went thru some wires. Its just expensive and time consuming . Let me know about yours too maybe we will figure it out.
Okay here we go again, the problem didnt get fixed have also problem with surges and the engine dies when I put on the brake sometimes it dies along with the orginal problem of reduced power and check engine, talk to some one with same vehicle , same year, same problem he has went to Izuzu dealership 10 times with no results cant figure out problem.

427hvn
03-21-2005, 08:44 PM
Okay here we go again, the problem didnt get fixed have also problem with surges and the engine dies when I put on the brake sometimes it dies along with the orginal problem of reduced power and check engine, talk to some one with same vehicle , same year, same problem he has went to Izuzu dealership 10 times with no results cant figure out problem.
MY RODEO IS FINALLY FIXED I TOOK THE "BRAIN" I DON'T KNOW THE RIGHT TERM FOR IT IT IS THE BOX THAT IS BEHIND THE DRIVERS SIDE FENDER WELL THAT THE HARNESS CONNECTS ALL THE WIRES INTO. I STRIPPED THE WIRING HARNESS LOOKING FOR BAD WIRES. NONE BUT AFTER PUTTING BOX BACK TOGETHER TIGHTENING THE BOLT THAT HOLDS IT ON AND TAPEING THE WIRING HARNESS BACK TOGETHER SHE RUNS BETTER THAN EVER. DON'T KNOW IF IT WAS THE BOX NOT BEING TIGHTENED OR THE WIRING HARNESS LOOSE OR WHAT BUT I HAVEN'T HAD ANY MORE PROBLEMS

richk5
05-03-2008, 11:26 AM
Here is the update on my 2000 Honda Passport (Isuzu) check engine / reduced power TPS problem.

After replacing the TPS (Throtle position sensor) with a new one and getting the same codes as before I assumed that I must have a wiring problem. It stands to reason that if the computer is sending out the same error codes before and after part replacement then there must be an information block. I started with the grounding issues because good grounding is essential. Earlier I found a broken bolt in the intake manifold that held a ground. It obviously looked secure but wasn't. I moved the ground to a secure bolt and for a short while the problem did resolve. Later the problem came back. This again seemed to point me in the direction of a wiring problem because there was an intermittent issuing going on. I cleaned and checked every other ground wire, added new grounding from the battery to the engine, and replaced the battery cables but that didn't help this time. I moved next to the computer. I wanted to check that every wire was secure in the socket and that it wasn't broken. Because there are so many wires it is a daunting task. I removed both the blue and red sockets running to the computer. I pulled both directions on every wire on the blue socket and all the wires were secure. I moved next to the red socket.

When I was about half way through that group of wires I pulled on one that seemed much less tight. I pulled a little harder and it slid right out of the harness. EUREKA! Now I had to find the other end of the break. I could by examining the end of the broken wire that it was shorted and as I dug through the bundle I found the other end. It was fused to another wire which was also partially if not completely shorted as well and the two had melted together somewhat. Fortunately I was able to identify which wire went where because both wires were color coded the same. I soldered the wires back together, reconnected the plugs to the computer and started the car. The reduced power light immediately went off. The engine accelerated for the first time in weeks and after a few starts the check engine light cleared and also turned off.

My theory is that the bad ground allowed an imballance of current in the circuit and the guilty wire overheated right in the middle of the harness bundle where the most heat would be prone to be concentrated and where the bundle was packed tightest together perhaps weakening the insulation protection and eventually a direct short resulted.

I hope this helps someone else with a similar problem because I had this car in two very competent shops and neither one of them could figure out the problem. I spent hundreds of dollars in diagnosis but in the end they told me I needed to take it to an Isuzu dealer who had the tailored diagnostic equipment. The closest dealer to my town is 150 miles away so I either had to trailer the car there or fix it myself, which is what I did.

I say the mechanics relied too much on the data coming from the computer and missing the possibility that the problem was not a component related failure but a wiring failure. Good luck to the rest of you.

204beast
05-08-2008, 11:24 PM
Here is the update on my 2000 Honda Passport (Isuzu) check engine / reduced power TPS problem.

After replacing the TPS (Throtle position sensor) with a new one and getting the same codes as before I assumed that I must have a wiring problem. It stands to reason that if the computer is sending out the same error codes before and after part replacement then there must be an information block. I started with the grounding issues because good grounding is essential. Earlier I found a broken bolt in the intake manifold that held a ground. It obviously looked secure but wasn't. I moved the ground to a secure bolt and for a short while the problem did resolve. Later the problem came back. This again seemed to point me in the direction of a wiring problem because there was an intermittent issuing going on. I cleaned and checked every other ground wire, added new grounding from the battery to the engine, and replaced the battery cables but that didn't help this time. I moved next to the computer. I wanted to check that every wire was secure in the socket and that it wasn't broken. Because there are so many wires it is a daunting task. I removed both the blue and red sockets running to the computer. I pulled both directions on every wire on the blue socket and all the wires were secure. I moved next to the red socket.

When I was about half way through that group of wires I pulled on one that seemed much less tight. I pulled a little harder and it slid right out of the harness. EUREKA! Now I had to find the other end of the break. I could by examining the end of the broken wire that it was shorted and as I dug through the bundle I found the other end. It was fused to another wire which was also partially if not completely shorted as well and the two had melted together somewhat. Fortunately I was able to identify which wire went where because both wires were color coded the same. I soldered the wires back together, reconnected the plugs to the computer and started the car. The reduced power light immediately went off. The engine accelerated for the first time in weeks and after a few starts the check engine light cleared and also turned off.

My theory is that the bad ground allowed an imballance of current in the circuit and the guilty wire overheated right in the middle of the harness bundle where the most heat would be prone to be concentrated and where the bundle was packed tightest together perhaps weakening the insulation protection and eventually a direct short resulted.

I hope this helps someone else with a similar problem because I had this car in two very competent shops and neither one of them could figure out the problem. I spent hundreds of dollars in diagnosis but in the end they told me I needed to take it to an Isuzu dealer who had the tailored diagnostic equipment. The closest dealer to my town is 150 miles away so I either had to trailer the car there or fix it myself, which is what I did.

I say the mechanics relied too much on the data coming from the computer and missing the possibility that the problem was not a component related failure but a wiring failure. Good luck to the rest of you.



i just started a post about this problem but now i got try it out hopefuly this will help

204beast
05-08-2008, 11:27 PM
Here is the update on my 2000 Honda Passport (Isuzu) check engine / reduced power TPS problem.

After replacing the TPS (Throtle position sensor) with a new one and getting the same codes as before I assumed that I must have a wiring problem. It stands to reason that if the computer is sending out the same error codes before and after part replacement then there must be an information block. I started with the grounding issues because good grounding is essential. Earlier I found a broken bolt in the intake manifold that held a ground. It obviously looked secure but wasn't. I moved the ground to a secure bolt and for a short while the problem did resolve. Later the problem came back. This again seemed to point me in the direction of a wiring problem because there was an intermittent issuing going on. I cleaned and checked every other ground wire, added new grounding from the battery to the engine, and replaced the battery cables but that didn't help this time. I moved next to the computer. I wanted to check that every wire was secure in the socket and that it wasn't broken. Because there are so many wires it is a daunting task. I removed both the blue and red sockets running to the computer. I pulled both directions on every wire on the blue socket and all the wires were secure. I moved next to the red socket.

When I was about half way through that group of wires I pulled on one that seemed much less tight. I pulled a little harder and it slid right out of the harness. EUREKA! Now I had to find the other end of the break. I could by examining the end of the broken wire that it was shorted and as I dug through the bundle I found the other end. It was fused to another wire which was also partially if not completely shorted as well and the two had melted together somewhat. Fortunately I was able to identify which wire went where because both wires were color coded the same. I soldered the wires back together, reconnected the plugs to the computer and started the car. The reduced power light immediately went off. The engine accelerated for the first time in weeks and after a few starts the check engine light cleared and also turned off.

My theory is that the bad ground allowed an imballance of current in the circuit and the guilty wire overheated right in the middle of the harness bundle where the most heat would be prone to be concentrated and where the bundle was packed tightest together perhaps weakening the insulation protection and eventually a direct short resulted.

I hope this helps someone else with a similar problem because I had this car in two very competent shops and neither one of them could figure out the problem. I spent hundreds of dollars in diagnosis but in the end they told me I needed to take it to an Isuzu dealer who had the tailored diagnostic equipment. The closest dealer to my town is 150 miles away so I either had to trailer the car there or fix it myself, which is what I did.

I say the mechanics relied too much on the data coming from the computer and missing the possibility that the problem was not a component related failure but a wiring failure. Good luck to the rest of you.


so which harness do i start on and where is it located??

richk5
05-11-2008, 11:36 PM
Start with the harness that terminates into the two connectors at the main computer. The main computer sits on the drivers side inner fender. Strip back the tape about 8". There are about 100 wires that pass through this bundle. Tug a little on each wire to make sure it is securely in the terminal fitting and on the other end where it goes toward the engine. If its a solid wire it wont give but if its burned inside it will stretch the insulation where it is fried and and pull out. Once you find it you need to solder it back together. There may be more than one burnt wire. Good Luck.

Quest4Boost
05-12-2008, 02:09 PM
Well, I just did this repair on my rodeo. I would start with the connector at the throttle actuator. Disconnect it and hook a multimeter to it. You can get a cheap one at auto zone if you dont have one. Measure at the connector with the red/white wire and you should recieve about 5 volts with the key on, ignition off. i recieved 4.94 volts. Then wiggle your harness and see if this voltage drops.. Mine dropped to about 3.4 volts then fluctuated back to 4.94 volts. Then comes the hard part, opening up the harness and replacing the wire. I just traced mine all the way to the ecu, to make sure I had the right wire, cut it and ran my own wire. Soldered the wires together and heat shrink. REchecked the voltage and wiggle test...wrapped it up and cleared codes. Thats it!! Only cost me 6 bucks for elec. tape, butane for my soldering iron, and a monster energy drink!! I found all my information in the FAQ section, under elec. problems.. I have a 2000 Rodeo 4wd ls 3.2l, and I was having similiar issues. No reduced power light, but my check engine light did come on once. Coming to a stop it would die. But it would fire right back up when I cycled the key. I did all the pre diag....checking intake manifold gaskets and alternator, even replaced the throttle actuator with a used one( a new one is $630 from the dealer) Mine cost me a $130. And still had the same problem intermittantly. Then I found the post in the FAQ section and it even tells you to check the "red/white" wire. So I hope this helps anyone having this problem. Happy Wheelin!!

I found a link to another thing you might want to do also to your throttle actuator. I'm going to give a try this weekend, and also throw some bilstein shocks on her. found it on planetisuzoo.com........................http://forum.planetisuzoo.com/viewtopic.php?t=14604

Steamfitter
11-02-2008, 07:01 PM
I had just posted about a problem separating front hub from the rotor,seems the driver side was unusually frozen the passenger side was way easier.
Now my brakes are great and while testing it almost died and reduced power lt. pops on.Let her sit fir 10 mins. and it fires up runs great on the road for a 5-10min test drive.
Now did I read correctly the red and white wire on drivers side harness was one prob/solution for this?
2001 v6 3.2L Rodeo Sport,it also had been intermittently lighting up the DTC.
If there is any new info out there please don't hesitate,it will be greatly appreciated.Thanks Carl

RunWithScissors
11-17-2013, 09:23 PM
I realize this is about 5 years since the last post in this thread, but Richk5 posted one of the best explanations of the problem I've seen. They are not all exactly the same though, but to say it's likely a broken wire when this problem rears its head would be a pretty safe bet.

Mine turned out to be a wire broken. 6 inches out of the ECM, it rubbed the frame until it wore through the insulation. Then it corroded. Then it caused too much resistance in that circuit and burned out part of the ECM Board.


I had looked into the TPS, cleaned all of it. Start it and get 0 volts to the top two wires that run the throttle body MOTOR. So, I assumed one of those two wires was broken. Stripped it all the way back to the ECM and all 8 wires coming from the throttle body to the ECM are good. Wiggle-test and tug-test good. So, I'm a little miffed and upset at this moment, because I was hoping to find the smoking gun.

I decided to open the ECM just because. I figured that was the cause now, since there was *some* response to the pedal (so it's likely not the APS in the pedal), the motor in the TBA worked, if I applied external voltage to it. The wiring was ok. So, it HAS to be the ECM, right?

Inside the ECM, I find a layer of smoke on the case, and some burnt parts on the board. Bingo. Smoking gun. I'm done. (If you think that, you've probably burnt out good parts chasing down the bad ones.) I know that I'm not really DONE, I need to find out WHY the board burnt.

The burn marks were right where the main board has the long feeder probes to the harness connections. Which connection was it? I sort that out by counting them from left to right... #9, top, on the red harness. Where does that wire go? I better chase that down. It's red with a green stripe. So is this one. And this one. And another. Damn there's a lot of those here. They kind of go in this mess and out there, so pull back and forth on both ends until you find the one that matches the pull.... oops, one just came out of the bundle. Corroded wire, worn insulation. Looks like the one that I was pulling on, but it's not. It goes to the pin above the burnt one. Where did that rub? Oh look, right there on the fender. NOW I have a smoking gun. Soldered in a new stretch of wire (I even put a FUSE in there, just in case). Back to the burnt terminal... it goes up to near the engine block and... wait for it... is spliced with the broken one and several others. What? Why do that? That makes no sense Isuzu/Honda/GMC. Oh well, we're now ready for a new ECM.



Photos to come in another post.

And the results of a "new" ECM install. (no way I'm paying over $1000 for an ECM for a car that's worth <$1000)

amigo-2k
11-18-2013, 07:23 PM
I would be interested is knowing where the rubbing happened so I can check to make sure it isn't happening on mine ....

nomoreuslesinfo
07-06-2014, 03:36 PM
To all the rodeo and passport people replacing parts, the problems are in the wires. I spent 2 hours reading post from some knowledgeable people and many dum dums. Before buying 02 sensors or throttle body valve. Test the wires.

Thanks to Quest4Boost

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