09 750 Brute force wont start

[dustrunner]

So the computer slows down the volts to the pump at idle ?

[ps2fixer]

On my Lexus car it does which is a 1990, on my dad's rincon, the fuel pump runs full speed always. Most older cars run the full pump at full speed. 2009 is a newer than most stuff I work with, so not sure if it's the norm or not. Have to love computer controlled stuff lol.

[dustrunner]

I'm on the hate side of computer stuff rite now, i got a corvette with electrical no spark problem, plus this atv, and a tractor that wont charge. But I will get my thinking cap out this week and see if something wonderful happens.

[ps2fixer]

Sounds like fun. Tractor is probably the easiest one if it's an older machine. Probably best for a new thread for each if you want more detailed input on them. Depending where the rectifier/regulator is for the tractor's alternator, you'd want to test for AC if it's external, or DC if it's internal. If no power, you'll need to figure out with wire powers the fields and make sure it has battery voltage. It should come from the ignition switch in most cases. Safety systems etc might effect it on newer stuff. Also of course if it's a junk battery, it won't hold a charge. Simple test for that though, take a battery voltage reading with the machine off, and a reading with it running, running voltage should be higher than off voltage if it's outputting power even with a bad battery.

How old is the corvette, it's kind of the same story with the tractor, older is much simpler, pretty much just have to make sure the distrubitor has power from the ignition switch and have good rotar, cap, plugs, wires. If no spark at that point, it's likely the module in the distributor (same thing as a CDI for our ATVs but wired/designed slightly different).

There's a reason I run old machines, they don't experience electrical problems that makes the machine completely useless. It's kind of like modern power tools, pretty much anything with a brushless motor is awesome, more battery life, more power output, etc, however a microcontroller is a requirement for the motor to work and that is the most likely point of failure unless the tool is designed like garbage. The old power tools it's just a motor and a switch, variable speed ones have a bit of a circuit board to step the power in the different levels but generally are very reliable.

Newest atv... 1987 TRX350D (I don't count the 1999 350 Warrior that I haven't rode in 10+ years).
Newest car I've own - 1997 Toyota Corolla (last year of the cast iron block engine, got 300k miles on it, bought it with 225k)
Newest Truck - 1998 Toyota T100 (last year for the T100's before it became the 2000 Tundra and built in USA, All T100's are built in Japan and I can see the build quality difference). The door pins on my T100 are perfect, never seen a Japanese built car/truck with bad/worn door pins yet, I have two Tundras for parts.... both door pins are very bad for the driver's door, one at 250k and the other at 350k miles.

Heck even my lawn mower is from the late 80's Honda. Orig plan was to fix up a 1963 Simplicity Landlord 2010, but the Honda has a better design in my eyes (full shaft drive to the transmission, I hate belt drive on mowers).

Only exception is computers, tv's/screens, etc, but I still stay clear from the "Smart" tv's and such. I'd rather hook a media computer up to it and let the computer be the "brain" that I can control what's going on.

I haven't had to work on my own vehicle for an actual issue since I've owned GM products, like the 1993 Pontiac Grand am with the not desirable "U" motor 2.5L. Bad module (pain to change), also did a tune up and one of the new spark plugs missed while under load, replaced them again and that was solved, then a couple months later, out of the blue head gasket blows. Went to the Astro Van I parked with the 4.3L v6 to fire it up and prep it to drive since I had it and was a daily driver like a month before then... distributor cap button fell apart and had no spark. Did the same tuneup on that machine just to drive it (it was destined for the scrap yard $100 beater). Had a worn out rear end with 220k miles. Drove a 1985 GMC S-15, fuel injected engine from a 87 truck but intake swapped back to carb + inline fuel pump, ran ok for low rpm, but it was garbage on the road with no power, only put 500 miles on it before I switched to a 1994 Ford Ranger I bought and fixed up. Came with a bad manual transmission (4th gear it would get stuck in) also had a locked up alternator (impact fixed it when we went to take the pulley off) and had to solder the starter wire from solenoid to starter motor. Swapped the transmissions out and spent a week trying to get the clutch system to bleed, even with a mighty vac, jacking the truck ad extreme angles etc. Gave up on the truck and scrapped it since it lacked power too (2.3L cal engine, later found out the primary coil was junk so the timing was retarded by running off the secondary coil pack). Long story short, I buy cheap vehicles and fix them up, these Japanese built machines hands down are 10x more reliable. My Camry I put 60k miles (240k -> 300k) on and has a rusted brake line, Corolla I put 80k miles (225k-305k) on and has rusted support for where the gas tank straps bolt on, 96 tacoma had the leave spring mount rust off on one side (the Dayna frame recall issue). I live in Michigan, so rust is normal and pretty much expected. I've only had the Lexus for about 1.5 years, I have a ton of work to do on it since the last owner hasn't done anything to it for the last 20 years, timing belt looks original and isn't long for this world, figured I'd do a major maintenance update on it since I know the 1UZ v8 is known to go 500k+ miles if taken care of. I've put about 10k miles on it (came with 217k and I think it's around 218k now). I've even taken the car out in the state land and followed my cousin's 4runner around, just didn't go through the big mud hole we ran into though. Even climbed a sand hill just as far as the 4runner with a little momentum lol.

I guess the TLDR is, from my experience, old Japanese stuff > USA designed, mexican/china made. Go back to old American made stuff and it's a bit harder to really say what's better, some of the old American stuff was really great.

Anyway, just to be clear, I'm not bashing anyone for owning american made or anything silly like that, just stating my experience. Kind of derailed from the topic a bit lol.

Wish I could live closer to people, electrical problems aren't fun, but they are always interesting to track down. My cousin poked at his 250sx for 2-3 days trying to figure out a no spark issue. Through messenger online, I had him do a few tests and in about 15 mins we figured out the kill switch wire was shorting to ground. Had him cut it since he said all the wiring was hooked up right and validated it runs. Ran a new external wire for the kill wire and found his reverse light was hooked up to the kill wire instead of the gray wire >.<. He muds the machine, so it's not exactly a pretty machine, and he can't afford another harness etc so hate advising the cut wire thing, but I know him so I knew he wouldn't care and I made a almost proper repair wire for him for free. Also sold him a new ignition switch at cost since his was bad (had to fiddle with it to get lights).

My dad's been calling me once in a while to help with electrical problems, and he's a trained mechanic. Sadly nothing interesting yet, just simple bad fuses and very easy to spot issues like people poking wires with meter leads and 3 years later nothing but green comes out of the hole cuz no one sealed it. It's acceptable practice in phone lines (business POTS lines), not automotive though.

I better end my post before I get my self into any more trouble lol. I guess I'm in story mode tonight.

[dustrunner]

As sharp as you are on Electric i'm suprised but agree on the older stuff is less problematic. the corvette is an 88 with the awesome VATS system I bypassed with a plug in ohm resistor I believe way back in 2006 . the tractor is an old 1950 ferguson 30 with original 6 volt system. got a generator on it with voltage reg. but im dumb. off to the shop to figure out the brute I hope ...

[ps2fixer]

I see, I personally haven't worked with generators on engines much, I think some where DC and some AC. If it has atleast 3 wires I'd assume AC (3 phase), just a single wire to the regulator I'd assume is DC. Photos probably would work best of the generator and regulator to show wires and such. I have a 1963 Simplicity with a generator, but it's only 1 wire and it's also the starter so just a basic DC brushed motor and has an external regulator.

I guess I'm kind of an interesting person, I'm the same way with tech, my career was in computers/tech/programming, however I don't even have an active cell phone, don't use facebook, twitter, etc. I'd rather go outside and waste time on a hopeless machine than waste time on social media. Just too much drama and junk on there that's just pointless to me.

I was hoping the corvette was around the 70's era, didn't really do much with 80's era vehicles, too much EPA emission garbage and vacuum line nightmares. The Toyota stuff doesn't seem to be plagued with that stuff as much. The 22R carb'ed engine did have quite a lot of vacuum lines though.

Had to look up the VATS thing, it's the chipped keys, yea those are not cheap, bypassing it seems like the logical direction to go xD. Too bad the signal is PWM else you could just bypass the whole security system. Might be an interesting product to look into for my micro controller adventure. Theory in mind is a small black box you wire in to remove your OEM security module that always sends the "good to go" signals to the ECM. Not sure if it's "keyed" in any way or if the signal is the same for all cars. I'm always looking for new stuff to make, should be a good learning experience, too bad I don't have the 93 Buick I scrapped out with that system..... I was going to fix it up but it suddenly lost spark when I car dolly'ed it to my dad's work to work on it (I was helping them so using the shop was kind of the agreement). I was only like 17 at the time though and didn't know a whole lot of this stuff.

Back to the micro controller thing, would be funny to build a "cracker" for the system so it tells you what resistance you need for the module. Assuming the 15 values are known, just go through them in a brute force style once per 5 mins to avoid the timeout effect. 15 * 5 mins = max of 75 mins to determine an unknown resistance value and it would be fully automated.

https://www.fastfieros.com/tech/gm_vats_passkey.htm

Anyway, unless you've done some bypassing on the starter relay, it sounds like if it's the VATS/passkey system you'd have no crank. I'd check for spark at the coil, should be the same style of test as at the spark plug wire, might have to switch a wire around for the spark plug connection, that's assuming it has a single coil and a distributor. If it has the coil packs and no spark, it's pretty common for those modules to go bad. I'd make sure your injectors are pulsing, which normally takes a "Noid" light which is basically an LED that lights up when there's a pulse. No pulse = computer not happy about something. If you have pulse, the computer should also be sending signal to spark too.

https://www.harborfreight.com/11-pie...iABEgJzjPD_BwE

I should be around the computer, so if you find anything out on the atv, post it up and I'll likely respond pretty quickly.

[dustrunner]

I PULLED THE PUMP out of the housing and pluged it into the main connector and have no motion in the pump with the key on. tried cycling the key on and off a few times but still no luck. but again the pump spins nice on a battery charger. The 88 corvette had the vats bypass in for years. Do you think the module would go bad ? it acted up a few times before finally not starting, but still turns over fine. thank again for your help.

[ps2fixer]

Hard to say on the Corvette, the Noid lights would probably be the best test to do, I'd think pretty much any mechanic shop should have a set of them, maybe the parts store would let you use a set with a deposit or something.

ATV's are a bit different designed vs a car, but I'd think the same way, if the computer is sending the spark signal, it should be running the fuel pump and injector. I can't recall if you checked for spark or not though. If no spark too, then I'd say it's some part of the safety system not playing nice. Also no spark could be caused by a bad crankshaft sensor but I'd think it would still run the fuel pump.

Looked over the diagram again, the ECU controls a fuel pump relay, so it's full 12v powered, so wiring that directly off a switched power wire should bypass the ECU causing issues with the fuel pump not running, but knowing why it's not running would be nice to figure out.

Scanned down the manual a bit, there's a million things saying might cause ECU damage, reversing polarity of the battery cables, don't charge the battery with the battery cables hooked up, don't disconnect the battery with the ignition switch on

Here's an interesting quote about the vehicle down sensor.

When the vehicle is down, the vehicle-down sensor is
turned OFF and the ECU shuts off the fuel injector and ignition
system. The FI indicator light (LCD) blinks but the service
code cannot be displayed. The ignition switch is left
ON. If the starter button is pushed, the electric starter turns
but the engine doesn’t start. To start the engine again, raise
the vehicle, turn the ignition switch OFF, and then ON. The
vehicle-down sensor is turned ON and the light goes OFF.

Also when you turn your key on, does the fuel injector light come on in the dash? If so, does it go out after around 2 seconds?

[dustrunner]

I will check the f.i. light tomorrow. This whole problem started after a snowy ride after my belt light came on = it must have over reved a bit in the snow drifts and caused the belt to slip upward and hit the worn belt switch ? I was able to use the jumper wire provided by kawi. hooked to the frame to reset the light for the belt. but that didn't fix it . also last time I messed with it fired rite up after spraying gas into the intakes.

[dustrunner]

I only see a belt light, a neutral light, an reverse light and an oil light across the top of dash and a fuel gauge to the left.

[dustrunner]

Vehicke Down Sensor = is this on the quad ? I will try jacking it up.

[dustrunner]

You are CORRECT AS ALWAYS ps2fixer = it does have a fi light that does come on for 2 seconds. I jacked it up and poured a lil gas in intakes and it runs till the gas is gone . so it is still getting spark.

[dustrunner]

ok, found a article that says that vehicle down sensor is farthest back under seat. off to shop hope this is it .

[dustrunner]

IT is still plugged in and in correct position but still no start. I shoulda stuck to 3 wheelers !

[ps2fixer]

From my understanding, the Fuel injection light coming on and going out after 2 seconds is "normal operation" aka no ECU codes and such. Pretty interesting the ECU isn't sending the signal to fire the fuel pump relay though.

If you want to jump the fuel pump, I think the easiest way would be right at the fuel pump relay. Could just do it temp to validate that's the problem. Possible the ECU has a bad circuit where it can't fire off the fuel pump or something along those lines, maybe from a bad fuel pump relay or it somehow got shorted out. According to the wire diagram, you should be jumping White/Red to White/Green and leave Yellow/Red and Brown/Yellow untouched or disconnected. The wire diagram isn't the greatest, so I'm unsure if the fuel pump will always run with the relay jumped, or only run while the ignition switch is on. I'd think it would only work with the switch on, but it's possible the relay is always seeing power on one of the switched legs.

If jump the relay works to make the machine run right etc and the fuel pump runs even with the key off, you'd be looking at modifying the harness to bypass the ECU. Looking like the Brown wire off the ignition switch would probably do what we'd want for the switched power wire. The ground comes from the ECU, so might have to hard wire the other wire to ground. Does the pump happen to come with a length of wire then a connector, or is the connector directly on the motor? Probably easiest to add a relay to the machine that switches on when the ignition switch is turned on, and it runs power direct to the fuel pump, while the other fuel pump wire is grounded. Should only have to tap into the harness at the brown wire for the ignition switch with that setup. To mod the fuel pump relay to work through the harness there would be a lot of cutting wires and such. Hopefully the fuel pump runs just normal with it jumped.

Just can't think of a situation where the ECU would be sending spark, no store codes, but not send the fuel pump signal, only case I can think of is a faulty ECU.