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P0100,102,103,104,105 &106 S-10 99' 4.3

Model: S-10 99' 4.3 Fault Code: P0100 Posted: 2017-04-07 11:29

Both MAF & MAP sensor codes. I did a volt test on both. It would seem that I have 0v on my ground going into the MAP. PCM is supplying 4.7, but 3rd wire is only getting 3.5 NOT 5v. Getting only 3v on my MAF also, and I think 0v on my ground there as well. Recently replaced fuel pump and grounded it directly as I believe it was not getting a ground from its original wire (old one was probably fine, just not grounded well come to find out). Is my PCM just acting stupid or is this in fact a bad ground situation all around?

Related fault codes
P0100P0102P0103P0105P0106
Comments (12)
Anonymous 2017-04-07 12:12

Truck ran (poorly) no codes then you replaced fuel pump. Resulting in the list of codes below. First thought is what wires did you ground at fuel pump - color of wire? Your comments " 0v on my ground going into the MAP" there should be 0 V on grounds. "Getting only 3v on my MAF " which wire? " I believe it was not getting a ground from its original wire" Why did you think bad ground? •P0100 Mass or Volume Air Flow "A" Circuit Malfunction •P0102 Mass or Volume Air Flow "A" Circuit Low Input •P0103 Mass or Volume Air Flow "A" Circuit High Input •P0104 Mass or Volume Air Flow "A" Circuit Intermittent •P0105 Manifold Absolute Pressure/Barometric Pressure Circuit Malfunction •P0106 Manifold Absolute Pressure/Barometric Pressure Circuit Range/Performance Problem

Anonymous 2017-04-08 06:44

as far as my fuel pump goes, I determined the ground was bad when I replaced the pump itself and rewired the new plug (from 4 prong cube to 4 prong strip), the ground wire going to the pump was not a good one, so I ran an entire solo ground to it. Wasn't activating when key went on, until I re-grounded it. This is why I suspect a bad ground in my truck itself, makes sense right? One ground is bad, then other systems go wacky, I believe it to be more bad ground. If I run my volt meter to the ground wire on the probed MAP plug then straight to the pos battery, shouldn't I get a 12v reading? 3 volts on the 5 volt power wire, and approx 4.5 on the MAP signal wire. I wanna stick with just the MAP sens for now, never mind the MAF for the time being, as I will mess with those readings again today at some point, because I could have been wrong on what I wrote about that.

Anonymous 2017-04-08 07:22

there was no codes befor R&R pump - I would look at that wiring. You needed to rewire connector for pump? That would suggest you did NOT use a OEM pump, Aftermarket are very very problematic - trade practice is use OEM here. Below is a wiring dia hope it helps you - http://www.revbase.com/BBBMotor/Wd/DownloadPdf?id=17840 Let us know your findings if you need more. PS - I want to confirm - fuel pump will not operate* if engine is not running. *will prime @5seconds the turn off. Less Time than going from cab to pump area.

Anonymous 2017-04-08 08:00

Diagram

Anonymous 2017-04-08 11:16

that's correct, no code prior to the pump failure or no SESoon light. Truck wouldn't start, and I know that 2-5 sec prime noise was not going off that's what led me to believe the pump was dead. Changed it, and it still didn't work, so I tested its ground and it had none. That's why I ran a new ground. Ran fine after that, then SES light came on after driving for a few weeks. Which brings me to the MAP & MAF code problem. I suck with diagnosing electrical, unless it's simple. And that diagram is appreciated but I had to change that plug from a cube to a strip , I do know the colors though, I wired it correctly. Truck starts fine, Idles fine, just runs bad and sputters driving

Anonymous 2017-04-08 11:26

I bought that pump after buying 3 that were wrong height for the tank, and all 4 had that wire connection change. It was NOT a cheap buy by any means.

Anonymous 2017-04-08 11:41

OK lets concentrate on current issue, you scanned and only posted codes, your scanner/code reader will show ALL P codes esp the P0999 and up so called manufacturers specific? Lets try BASICS - MAP sensor 3 wire KOEO gray wire - voltage @5v Black wire - no voltage and good ground Lt GRN wire - this is the signal should be @ 4.7v And what are you getting? MAF is also 3 wires NOTE do not use a K&N type filter a no no. Pink wire 12v - yes no? Black wire -no voltage and good ground Yellow - this is MAF signal and is reported in Hz will need a tester able to read Hertz.

Anonymous 2017-04-08 15:08

MAF pink wire- 0v yellow- 5v reference black- when checking solid ground to the battery, I got 0. A solid ground when checked against the battery's pos term should register 12v correct? not sure what you mean by K&N filter MAP grey-4v Lt grn-4.7 blk- again running to the pos bat I got 0v two bad grounds on both. I'm not a novice, but not an expert either. Best I can tell is I got no juice or ground going to my MAF and a bad ground on the MAP

Anonymous 2017-04-08 15:10

I know about the htz on the MAF and don't have that tester, but it should register 5v reference from the PCM correct? Which it does.

Anonymous 2017-04-08 15:15

so my big question is this: How do I correct the circuit? Where do I start? If it is indeed a circuit issue. If MAP probe is not grounded, and MAF is not getting volts, then I'm lead to believe it's a circuit problem and both units function properly.

Anonymous 2017-04-08 16:01

K&N is a type of air filter. Lets do MAF first. pink wire KOEO you show 0 volts... above diagrams #11 shows circuit - BLK/WT wire - ground yes a test light clipped on pos battery should light if this wire probed. >> I suspect wiring as a bad fuse would have other codes. Most wiring fails @3" of connector, MAF connectors are common fail.. wells part # 462 -that common MAP the gray wire is only 4.0v so the signal is unlikely 4.7. UNLESS KOEO MAP unplugged check for voltage on BLK wire....

Anonymous 2017-04-08 17:14

I gathered that K&N was the Air Filter, I just was asking what K&N MEANS. I DID NOT use a 'test light' to see if I have ground, I used the same volt meter. I use test lights to find ground to ground to, not in an electrical testing procedure. Told you I was not a novice. I'm simply trying to find my problem. I don't know how much more clear I can be when explaining things. So far everything you've relayed to me have been things I already know to a certain point. Like the wiring of my fuel pump, what the codes stand for from my OBDII scan, the purpose of the colors on each wire going to my MAP & MAF. Guess I will just have to put my trust into a good Mechanic. Thank you for your time.