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zakruti.com » Auto & Vehicles » South Main Auto Repair
I Go Off Into The Weeds With Tunnel Vision

I Go Off Into The Weeds With Tunnel Vision

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Rating: 4.0; Vote: 1
I Go Off Into The Weeds With Tunnel Vision Channel video: South Main Auto Repair - Category: Auto & Vehicles
Date: 2025-11-01

Comments and reviews: 20


16 year old car, 9000 miles on the odo, how does the gas smell: D
Here's my never-stayed-at-a-Holiday-Inn opinion.
2: 30 to 2: 37, that current graph for the pump looks all kinds of ugly.
you had 500ms/div on that first recording, you just goofed and killed the data by changing it. :)
When you tried to start at 3: 32, you can see the car cranked but the pump didn't start immediately, and then died 5 seconds later. See how the current died at that point but the voltage didn't In fact you can see the voltage trace wiggling as it decays. That's the pump spinning and back feeding voltage into an open circuit.
Your 5: 11 crank attempt, the spike was the relay latches but the contacts have failed. 3 seconds later the contacts allow current flow and the pump fires up, but using the power of the internet, we already learned from the future time that, the fuel system clearly has a MASSIVE amount of fuel in it, from the engine running for a LONG time without a working fuel pump. The 6 seconds the pump was on wasn't enough to prime the system it I'm guessing. )
5: 23's start the relay fails to latch, you hear the engine sputter (some fuel finally made it up there.
5: 35 when that second spike trace pops up, you can hear a noise that sounds an awful lot like a click. Possibly the relay unlatching.
5: 39 there's no spike on that crank attempt. This is a guess, but i'm betting the contacts at this point are all kinds of dirty.
Now what we don't know is what you did between then and 6: 48 to get the car running.
Finally at 8: 21 you're toggling the pump on and off, and it's working.
My theory: the relay contacts have/had corrosion on them. Intermittently they'd stop allowing current flow, killing the pump. When you got to the final step of toggling the relay, you basically cleaned the contacts in the relay by cycling it so much, getting it nice and warm, and the micro arcing inside every mechanical relay helped clean any corrosion or debris (bug spider webbing whatever other crazy organic material that manages to get into impossible places) in the relay from the contact points.
I bet this doesn't come back for at least quite a while, and if it does the relay will finally have quit.
) anecdote: Wife ran her 05 Dodge Stratus 2. 7L out of gas one night. I go out with the 'can and rescue her. 5 cranks, no start. Did the key on--off without attempting to start about 6 times, each time listening to the fuel pump. Stopped doing it when no more pump noise. Car fired up immediately on next crank. Similar deal when someone ran out of gas in front of my house (think that was an Audi, but something with a key and not push button start)

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I do not want to make it sound like I am in any way certain that my story is the same thing going on here, so read this with a shovelful of salt:
My 2000 Jeep Cherokee (4. 0L, 4x4, automatic) had a problem at one point where I would start it and it ran a little rough and then smoothed out and ran fine. I used it several times without that symptom coming back and no MIL. Then it came back, and to keep her from stalling I had to hit the pedal. Then it smoothed out and it was fine. I used it several more times with no issue and no MIL at any point. Then one day I started it and it ran rough and I drove it while it ran that way, expecting it to smooth out and it didn't. Then it just quit. Still, no MIL.
So why no MIL Because when the crank sensor fails you don't get one. Are all OBD-II systems run through the crankshaft positioning sensor that way I'm not sure, but I know that when they are, you don't get anything about anything. (I almost suspected the fuel pump was intermittent because that's how the original pump failed, but the pump in the tank was pretty new when this happened)
Also, I have had several different vehicles with failing crank sensors and they seemed to all exhibit different symptoms. The very first one REALLY made no sense because one day the car just wouldn't start; that was it. No sputtering, no warning of any kind during any previous use. (It was a Ford)
My point is that I researched the symptoms of a failing crank sensor on that Jeep and not only did the typical symptoms not match mine AT ALL, but two seasoned mechanics (one of them was nearing retirement) told me there was no way it was the crank sensor. I pulled it and tested it, anyway. It was NFG.
All I'm saying is that when I hear no codes and a stalling condition, I think it's worth testing that part. Especially since the symptoms do seem to vary.
And the exhaust sounds GREAT.
And was that an Astro in the background Those have a place in my heart, too.

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As a older challenger owner myself; I'm assuming it would've been the fuel trims fighting the new exhaust; my reasoning being that I had installed some new shorty headers BUT crushed the collector in a fit of rage(Not enough to trigger a CEL, BUT enough that the fumes would travel up the firewall and into the HVAC. Wasn't too big of an issue, but once in a blue moon when the car was leaning right; it would open it up just right to stall it out and sputter until I could creep forward enough to have it seal without triggering a CEL. Now further down the road i've installed some nice long tubes and the issue never returned.
I will add, contrary to popular belief that the downstream O2s(atleast in my 2014 challenger 5. 7 w/ 6spd and the lack of emissions equpiment minus exhaust valve VVT from the factory) DOES affect the trims.

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Man, it must be this month. Nothing to the extent of what you're dealing with, however I was barking up the wrong tree with some EVAP Lean codes on a VW Tiguan. Now experience with that year range of VW showed me its the N80 (Purge Valve) or Purge Tank near the filler neck that take a crap or degrade. Smoke tested, saw some leakage at the purge valve and said Yup, that checks out. For some weird reason, my friend Albert asked if I checked the gas cap, which I didn't since it wasn't a gross leak code. I ran it on the good ol' Commonwealth of PA's emissions machine and lo behold the gas cap was starting to leak. Thank God he mentioned something because the last thing I ever want is to have a customer spend more than they have to and get them back on the road.
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So here’s my question to you folks: what would you do next I had the car running for hours without a hiccup, so where do you go from there Even though I was off the mark at first, the info gathered is still useful. Why Because knowing what’s NOT wrong is just as valuable as finding what is.
In this case, we know it’s not a fuel pump issue. We know if there was a control-side relay issue (fuel pump or ASD, it would set a code. We also know that even with fuel pressure, it still wouldn’t start at least once. That points toward something cutting spark or injector pulse without throwing a code.
That’s where I’m at. Still chewing on it. and still waiting for the customer to call back and say it finally died. I hate waiting, haha.

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this classifies as an there I fixed it moment.
ahh, the joys of things randomly breaking at the perfect(wrong) time. or like new air shocks having a hole and leaking out the middle of the rubber, had to have been factory poked or someone did it on purpose along the way from factory to me. worst part is, my preliminary inspection/testing before installing didn't catch it, because I didn't solid connect a line and run the pressure up high. oh-well, trashed the still holding air, but leaked fluid/no dampening left pair of air shocks from 2010 and bolted on the used but good standard shocks I've left laying in the garage under bench since then. those old sears road handler's were some tough suckers that lasted.

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Eric back in 2009 I bought a Journey and in the first year it did exactly what is happening to you. I had it to the Dealer 11 times where you would just be driving and it would die. Sometimes it would restart sometimes not. If you let it set for a few hours it would start and be good for several days then start again. The dealer through the parts cnnon at it and replaced everything you can think of 9Fuel Pump, harness to pump, TIPM, Engine computer, entire wiring harness, all the sensors and on and on. Finally found the battery in the key FOB was weak and would just randomly turn off car and never would through a code. They ended up replacing the ignition module and key Fob never had a problem again.
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I just went through this exact problem with a 2014 Ford PIU. I spent hours investigating the fuel pump, fuel pump control module, fuel pump relay, and fuel pressure. I moved onto the spark side of the equation. At first it appeared to have power at the coils and I went to test the pcm's ability to ground the coils and the vehicle started, so I was not able to find the problem initially. Finally the vehicle would crank no start again and I finally found that it was intermittent power to the coils. The female side of the coil fuse was loose so the fuse was not making constant contact. I used a pick to bend the female side of the fuse block hole tighter, making the fuse stick in properly.
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These pushbutton start Chryslers are quirky. I've seen it happen in the shop a few times where the ignition is left in the on position for a period of time, then the engine will crank but not start afterward. If the ignition is cycled back off, then on again, the engine will start. Since this car has a code for a low key fob battery, I'd likely start with the simple stuff first and verify the key fob battery is good. The car seems to be behaving like it's doing an anti-theft shutdown rather than a random stall. I remember from Chrysler's service data that the engine will start but stall after a few seconds during a theft event. They're different than other manufacturers.
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This video is actually an excellent example of a few things. First, just because something smells like something it may not be (a. k. a. dead fuel pump. It also tells us that just because everything sounds like a specific failure, test it BEFORE you toss parts at it. If you had bought a new fuel pump it may not have resolved the issue. Also, I'm wondering if it could be a fuel pump failure. If the pump electronically fails, wouldn't it be possible the amps and voltage could drop to zero because nothing is being drawn by the pump (I am a desert tree type of mechanic, meaning I know less that very little about automotive repairs which is why I love Eric's material.
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FYI the car will continue running not necessarily because there's residual fuel pressure but because the pressure drop across the injectors and the relatively low fuel demand, the fuel trims can often be enough to keep it running. I noticed this on my 04 cobra. wanted to service the fuel rail so decided to start it up then turn the pumps off to drain the fuel out of the rails (similar to what you'd do on a carb. fuel pressure went to 0, car was chugging but it kept running with the fuel trims pegged, pressure drop was enough to pull fuel thru the pumps and into the system. eventually had to just turn it off: P
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You may have inspired me to see if I can get my '94 Dodge Caravan running again. I put a fuel pump in it a couple of years ago and it hasn't been driven more than 50 miles since and sets for long periods without being run. I guess I waited too long this last time and it won't start, it cranks just fine but I didn't hear the fuel pump so I assumed that it is stuck since the fuse is good. Now I have to check the relay and bang the tank also. It was my late wifes van and I just keep hanging on to it when I should have let it go long ago. Probably need to check for spark also though it has never failed.
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If it's not gettin' a voltage reading but it's drawing current, what ever those things are, the load of that circuit is gobbling up the voltage, do we know that I can't afford one of those fancy amp clamps so I'm not sure who's actually using up all kerchoff's push. My brain's going alternator no battery no relay What's a relay again oh yeah a switch. So at 12: 58 I still could not eliminate any reason why the car would not start. Is it out of gas I don't know. But I did learn a bit more than I knew yesterday. Unfortunately I have no idea what problem is. I can't wait to see how this one ends.
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Several years ago a coworker bought a new Mustang. Had it for a couple of years when for one reason or another he rode in the back seat with someone else driving. On occasion the engine would stall out, but only when he was in the back seat! The short story is he found the fuel pump harness slightly misrouted under that seat. When he placed his weight on the seat just right, a seat bracket would chafe into the harness shorting it out. When his weight was removed, the fuel pump operated normally. I noticed you had the rear bottom seat resting on the roof. That reminded me of this story.
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I noticed 5: 12 Start Cranking = transient but pump didn't start, 5: 14 continued cranking pump on, 5: 20 Stop cranking (pump off, 5: 24 Start Cranking = transient but pump off, 5: 40 Start Cranking but NO transient. I would have then scoped the relay control circuit to correlate that circuit during transients and cranking. I also wonder about the period of those transients. The symptom at 5: 40 could be an ECM safe mode. Question: Does the ECM have any sensing of the pump current Maybe the ECM is sometimes unhappy with pump current during crank (but how would it sense that.
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I had a early model Charger with the 5. 7, I'm not sure if this Challenger has the same system, but my Charger was pretty much doing the same thing, took it to a ton of shops, in the end I went through some forums, I was able to find out that in the fuel tank there's a weird funky sensor. Not part of the fuel pump, but embedded onto the wall of the fuel tank. Apparently that sensor manages the fuel as well, long story short, it is a recall and the dealer ship replaced the entire tank with the sensor free of charge. Something for y'all to look at maybe. Keep us posted!
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First observation is 7. 000 miles in 16 years, so it can be anything related. Bad fuel in the lines Maybe look for rodent damage Humidity can corrode plugs.
Second: it looks like it's running better when warmed up. Could still be a corroded plug, they tend to 'uncorrode' when in use. Rodent damage not so much, because it would reoccur then. Bad fuel could still be an option, since it's now clearing the lines. But then again I don't see smoke out of the exhaust.
My best guess is a corroded plug. Somewhere. Ask the guy where the vehicle is stored.

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I had this problem on a pro master van in the dealer couldn't figure it out and it was the automatic shutdown relay would only latch every once in a while. Funny how that same Mopar relay has been in everything forever but the new ones say fiat on them I swapped the ASD relay with the horn relay Bob's your uncle had started $800 at the dealer with no clear fix minutes and actually how I figured out as I took the cover off the relay Shoved a piece of wire in the contact. Mine was a lot simpler though I did have an ASD relay code.
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14% is high, but if were speaking completely realistically. 6-7% is prime apr% right now. The 14% is probably a baseline for this guys credit, he probably between 640-690 F. I. C. O.
But the smart move for Mike ( the bald bearded shorter guy ) would have been to pull all 3 credit reports. Find out which of the 3 bureaus are the highest of the scores & then seek a local credit union or bank that strictly pulls that bureau where his score is the highest. Then apply for a loan through them. Probably would be at 9-11 % apr.

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Still runs without a fuel pump. Son of Christine! Eons ago me and my buddy's tuned up my 64 Corvette, or so we thought.
Stalled after it got warm. In the middle of morning- rush traffic. The only one of us with diagnostic tools, narrowed it down quickly.
We didn't replace the condenser. Remember them They never go bad
16 years old Look under the dash for unplugged or under-plugged wires Vermin signs. Chrysler's famous rotting dashes.
Maybe Mrs. O has some insight on the matter!

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