'17 Chevy Traverse Crank No Start
Owner says vehicle died while idling at McDonald. Started and died again but wouldn't start since.
FF for P018B shows open loop status, 87.7% engine load, ECT 213 deg, FPS is low at 20.45 psi, FRP low at 58.02 psi, fuel level at 31.8%. Fuel pump runs when commanded on by scanner and with KOEO. No FF for P2635.
Live data with KOEO shows about the same pressure numbers as in the freeze frame. Desired fuel pressure @ 72.66psi, FRP @ around 2 psi. Found a TSB about potential lying fuel level sender but couldn't locate connector x350 mentioned in the the TSB to ohm FLS. I was able to ramp FP speeds up to 100% and it was spinning faster.
I got the vehicle to start while having the right rear jacked up, but it died immediately. I think either gauge is lying and fuel is too low or there is a restriction at the pickup between the primary and the secondary inside the tank. So i think it's time to drop the tank. What do you guys think?
Edit: It's a AWD model wit 32k miles. Thanks
Lesage what you're saying makes sense based on the symptom. I haven't had a chance to research the setup on this car or any of the codes. I'll check my service info to see if I can get you an idea of where X350 is. That said, I'd add a couple gallons of gas & see if the car then starts & if the gauge as well as scan tool pids change accordingly. Just my initial thought, I'll get back…
Awesome Zachary, i was just thinking about getting some fuel to test it. Thanks for the reply.
How many amps is the pump drawing? If there is no fuel to move, then there should be a low amp draw.
Good point Mike. That'd be a quick non-invasive test. High rpms as well if current ramping with a scope.
Great point about the scope and pump speed. I really need to get more into scope testing and keep a notebook of normal values for things like pump speed
Mike I know what you mean. I'm probably somewhere between a beginner & intermediate level scope user. Lately I've been trying to use it as often as possible just to gain more experience and gather know goods. Always learning right?
Zachary, definitely always learning. That is why I really like forums like this. I help where I can and I learn where I can.
Thanks for the idea but I had no means to check for amp draw.
Actually i just replaced a fuse on my DVOM but i didn't have it on me at the time to connect it in series in the FP circuit.
Most decent meters have a DC ammeter built in for up to 10 amps. You can even use an old VAT-40 or similar load tester's amp clamp. If you want more resolution make 10 coils of primary wire and zip tie them tight. Then install the wire in series in the circuit. The VAT-40 will read 10 times the circuit amperage. Or you could get an Innova 3320 for about $25 on Amazon. It isn't a great meter…
I agree with Mike, fuel pump current will answer a lot of questions about the pump and fuel level. I'd expect about one amp with a good pump and an empty tank.
Remember the pump is controlled by the fuel pump driver module. It has constantly varying amperage due to the fact that it is pulse width modulated by the pump. If your going to current ramp the pump unplug the fuel pump driver module and jumper across the connector to bypass the module and hardwire the pump. Easy peasy done it many times. Or you could just put some gas in it lol.
That's a good point Caleb. I wonder if the scan tool control he used to ramp pump speed up to 100% allows for this as well. Or if it's like other PWM controlled devices where "full on" means 85% or something similar. I suppose if you had a known good waveform for cranking conditions on one of these, you may still notice a difference between current draw with & current draw without fuel. Just…
Yeah I could geek out and scope out the pump's current but I don't have an oscilloscope.
Thanks Caleb. Yeah the FPCM works similar to Ford units. Scope would be high tech for me but I don't own 1.
So thanks everyone for the help. I concluded that the fuel was too low by simple deduction. I was gonna go for the p2635 instead of p018b because according to code criteria p2635 runs if p018 is not set. Consequently p2635 must have set before p018b. P2635 was gonna lead me down the path of the FPCM but I abandoned that idea before even starting. Because looking at the low and high fuel pump…
If you dont find the question offensive Lesage may I ask why you do not own a scope??
Hi Caleb. Another good question is, why do I own four, and never need any of them?...LOL....Oh! I remember....if I get rid of them I WILL need them. That's one of "Murphy's Laws", iirc. I even just got the adapter for my Mastertech, I love the old stuff! youtube.com/watch?v=kdcFbO…
Not at all my friend. I'm a very small operation and couldn't afford it, but next year God willing i'll get one.
Check out the uScope from AES Wave. It is small and cheap, but a powerful tool. I think it is about $160.
For another 200 bucks you can get the autel 4 channel scope
How good and reliable is the Autel scope Randy. To answer your ? about the meter it's not no fancy fluke 87 or 88 but a lowly craftsman I've had for over a decade.
I hear you. Do you own an Autel scope?
Yes own autel and a pico and a u scope and a old hanteck
So how does the autel compare to other ones? Is it reliable and consistent?
it is a descent scope for the price much better than the hanteck butt not as good as a pico . But you need start with something
I know about the uscope. I don't like to own superfluous amount of tools. I'll wait for at least a 2-chanel.
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