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Post by unimog1300 on Apr 28, 2005 17:40:40 GMT -5
Hi list, My name is Mike and I hale from Packwood, Washington. I have been reviewing the posts regarding fuel pump problems, and have found nothing that pans out. So here is my storie. I have a 1994 Sidekick with the 16 valve engine and 165000 miles on it. I travel over a mountain pass three to five days a week. When I returned to my truck after a 12 hour night, all it would do is turn over. All the fuses under the dash are OK. So I had it towed to the Yakima Suzuki dealer. They told me I needed a new fuel pump, to the tune of $650usd, ouch. It felt like I was being rodded. So I elected to have it towed home. It ran perfectly when I got to work, but when I got off shift, it didnt even think about starting. Also I pulled to timing cover off and the belt was still there. I havnt bought a manual for it yet, but I suspect that one is in the cards. Who makes the best manual. If in fact it is the fuel pump, can I just put an inline pump on and draw fuel through the intank pump? I really have enjoyed this rig in the short time Ive had it. We drive it pretty hard offroad. I just hope I can fix it my self. Thanks for your time, and sorry about the lingth of my first post. Mike
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Post by louthepou on Apr 28, 2005 17:59:38 GMT -5
Hi there Unimog,
Chances are, it could be the fuel pump indeed, but it may also be the wires going to the pump - check for rusted-through back side of the rear passenger side wheel well. If it's got a hole, the wiring harness might also start to rust, thus intermittent problems.
If the pump is going indeed, shop around - different dealers, both Suzuk and Chevy, then aftermarket (I think in the States, that would refer to things like Autozone).
Good luck, keep us posted.
Louis
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Post by 95sunrun on Apr 29, 2005 21:59:14 GMT -5
on top of the tank there is a ground wire soldered to the sender unit. my friends 91 Tracker had a intermitent stall/no start that rendered the fuel pump dead. Fixed the wire that had turned green and fallen apart (the ground wire soldered on the sender) and bingo, runs like a champ. Which is good cause the fuel pump itself is expensive!
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Post by unimog1300 on Apr 30, 2005 12:07:06 GMT -5
Louis, Ive ordered a manual for my truck, but it will take a couple of weeks to get here. The joys of living in the woods. Is there someone on the list that will help me figure out which harness to test? I read all the posts on fuel pumps and found one that stated behind the left rear taillight is a plug with two heavy pink wires. And this is for the pump. But I dont have anything like that. There are a few plugs in that area, and the two that I have tested are. #1 a triangular plug with 3 wires going in and only two going out, fairly light gage. With the key off I get 5.1 volts between white and black, and nothing off of the other wire. With the key on I get 5.1volts between the white and tan too. What I really would like to know is if there is a way to jumper 12volts from the battery directly to the pump. If there is what plug do I use and what wires. #2 plug that I worked with a little is rectangular with 9 wires in and 9 wires out. It does have a heavy gage pink wire run through it but I couldnt get anything out of them. Please help the gas mileage on my pickup is killing me. Thanks Mike
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Gman
Counts zuks instead of sheep
Posts: 530
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Post by Gman on Apr 30, 2005 22:53:48 GMT -5
Thanks, Ray and welcome to the Forum That is one of the most informative postings I've read in a while ... I'll double check of course, but it could direct us to the right wire to use to test fuel pumps... a first recommendation to future members, posting a fuel pump suspicion of failure, that is... You are saying the pink w/ the (either blue or black) stripe could be jumped to 12v, to test fuel pump while the solid pink wire could be replaced with a jumper (question is does the ECM energize it or ground it ??) to test the relay... Now we're saving people a lot of time... (Assuming this can be proven) cause the relays (on the bottom of the ECM, are not that hard to get to; and if you knew exactly which color wire... it could be a VERY SIMPLE TEST... Keep up the good work Jeff
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Ray
New Member
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Post by Ray on May 1, 2005 2:53:58 GMT -5
Jeff:
It's not that simple with the pink wire, since this wire is used by the ECM to control the fuel pump relay. The B/W wire does not bring power to the fuel pump. It may be a bad idea to jumper the pink wire, since at least for what I can tell by looking at the diagram, this pink wire between the ECM to the fuel pump relay may well be a negative signal to energize the relay. If so, jumping this wire could damage the ECM.
I made a terrible mistake in my last post, because I was looking at a diagram that does not show much of the details. I got the Suzuki manual from my garage, and this is what is going on:
1. Power from the battery goes across the main relay (it never goes across the ignition switch). The main relay is energized by the ECM, and now the 12 VDC from the battery is transfered across the main relay on a wire marked BL/B. This BL/B wire is the one that eventually will reach the fuel pump (explained below).
2. This 12 VDC across the main relay goes to the fuel pump relay, but not across it. It just stands there until the ECM energizes the fuel pump relay. Once the ECM energizes this relay, the 12 VDC on the BL/B wire goes across the relay straight to the fuel pump.
3. Power to the fuel pump relay comes across the ignition switch on the B/W wire, but this power does not energize the relay. It just stands there at one side of the coil. The pink wire from the ECM is connected to the ground (-) side of the coil. I imagine that the ECM provides the ground signal to the fuel pump relay's coil, the relay energizes, and the 12 VDC power on the BL/B wire now goes across the fuel pump relay to the pump. --------
Summary:
-Pink wire = maybe ground signal from the ECM to the ground side of the fuel pump relay's coil.
-BL/B wire = power to the fuel pump
-B/W wire = power to the + side of the fuel pump relay's coil.
-The fuel pump has its own ground wire. It should be grounded somewhere not too far from the pump.
I went back and deleted my previous post, and would like to I apologize if I have caused some misunderstandings.
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Post by louthepou on May 1, 2005 6:29:10 GMT -5
So, you are not perfect? Not to worry, neither am I, and I suspect a few other members could humbly admit that too. A few members are good with wires, though. Jeff's already helped a few desperate souls, and others will pitch in, no doubt (eventually)... Louis
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Gman
Counts zuks instead of sheep
Posts: 530
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Post by Gman on May 1, 2005 13:39:21 GMT -5
Well you did fine in my opinion, nothing really misleading... only explained in more detail the second time. I noticed you left out the pink stripe wire which does exist somewhere at least at the rear of the vehicle...
(written earlier) I noticed the engineers like to use the same relays in that area and since the horn relay grounds to become activated... it was in my mind already that the fuel pump relay would likely need a grounding signal, as well...
I noted the un-shurity and I should say that I would pull the plug off the fuel pump relay... find the solid pink and release it from the socket with a sharp object... then my jumper wire could be stuffed into the area (and I would try grounding first) but supplying 12v to a terminal thats supposed to be grounded is not likely to harm the switch... it just won't work until it gets the right signal...
Jeff
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Ray
New Member
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Post by Ray on May 1, 2005 14:37:47 GMT -5
I agree with you, Jeff. I have heard that some folks have found the fuel pump ground wire terminal (at the grounding point) loose or full of dirt. If this happens, the fuel pump could stop working. According to the instructions in the manual, if one removes the fuel filler cap, and then have someone turn the ignition switch to get all the accessories going (including the ECM), one should be able to hear the fuel pump working for a couple of seconds. Keep in mind that if the fuel is already pressurized, the pump won't come on. But if the fuel is pressurized, then the pump is working According to the manual, the ECM controls the fuel pump via the fuel pump relay. The ECM turns the relay on for 3 seconds after the ignition switch is turned ON, while the switch is turned to START (to start the motor), and while CMP sensor (??) signal is inputted to the ECM. I have the Suzuki Sidekick Supplementary Service manual. The wiring diagram in the troubleshooting section does not show the wire colors from the fuel pump relay. The colors are shown in the engine wiring diagram at the back of the manual. According to diagram in page 1-1 (USA Spec. Vehicle with 1-Cam 16-Valve Engine), the wire from the fuel pump relay to the fuel pump is "P/B" color, and the fuel pump ground wire is "B" color. The problem I see when using jumper wires is that sending 12 volts to the wrong location around the fuel tank could blow up something. That's the reason why one should disconnect the battery before bleeding the fuel pressure at the bleeder port. I would carefully check the ground wire to the pump first. Maybe the problem is there.
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Gman
Counts zuks instead of sheep
Posts: 530
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Post by Gman on May 1, 2005 23:18:21 GMT -5
Just to follow up on the wiring colors to the fuel pump relay...
I looked at a '93 8 valve wiring harness...
Found the green socket plugged on one of the relays... then I found the black stripe that provides power to the relay... and the pink, which I traced to a plug on the ECM finally I found the pink striped wire that led to the socket that plugs into the rear wiring harness (and goes to the tank)
SO you could pull the green plug and jump across the black stripe to the pink stripe to test the fuel pump...
OR you can remove the pink wire in the socket and substitute a grounded jumper there in its place to test both the relay and the fuel pump ( though it would be just easier to swap the sockets to the other identical relay there beside it... cause they both would not be bad at the same time)
Thanks Ray,
Jeff
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Post by unimog1300 on May 2, 2005 16:08:57 GMT -5
Ok, this is a lot of info. Let me follow up to were I am at now. I tested the relay under the dash, and it is working properly. I found a blown fuse that appears to control the marker lights and the factory alarm. And I am curious, I have no scematic to tell me what each fuse under the dash goes to. Not in the manual(that arrived early) nor anywhere in the vehicle. And the fuse block itself is not labeled. Also, once I made sure that the relay was working, I went to the pink wire behind the left rear taillight. Im not getting any from it at the plug located there. And I think according to the wiring scematic in the manual, that this is the correct wire to test. And that is where Im at. Thanks Mike
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Ray
New Member
Posts: 6
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Post by Ray on May 2, 2005 22:09:23 GMT -5
From the fuel control relay to the fuel pump the power wire should be P/B color. I imagine that this wire is pink/black color, not just pink. The pump's ground wire should be black color.
The pump shares the same ground as the side markers and the rear combination lights, however.
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Post by tuckerx1111 on May 3, 2005 7:36:18 GMT -5
when your vehicle is in a no start mode, try having someone hold the key in the on position while you thump the gas tank with a lug wrench or something simular. If this causes the vehicle to start, then you know it is the fuel pump failing. note--this sometimes works but not always
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Post by unimog1300 on May 3, 2005 19:24:46 GMT -5
OK, Pump is out of the tank and out of service. Ive called around and found prices in the $250 area. All the parts houses asked if it was a soft top or a hard top. None of them cared if it was 4door or how many valves it has. So can I use a pump out of the same year 2 door hard top? I found online a place called "efuelpumps.com" and they had the pump on slale for $79.95! Dont know if it is a remanufactured unit but does it matter? Also found a web page that has Python Injection Inc. pumps that are remans for $100.00. What do you guys think I should do? At this time Im leaning toward the 79 dollar one. Let me know Mike
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Post by tuckerx1111 on May 3, 2005 20:18:56 GMT -5
$79 sounds great to me. I paid $150 Canadian for a used one. It came out of a 91 2 door and went into a 94 4 door. Looked different but is still working 2 yrs later.
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