17 cat 299d2 crank no start.

The Systems Operation for your Tier4 final/Euro IV fuel system states:

The valve is opened and closed by the ON/OFF of energizing the PCV [Pre-stroke Control Valve - fancy way of describing the fuel pump controller], which is controlled by the Engine ECM. The ON/OFF timing is controlled based on signals from various sensors to provide optimal rail pressure.

If you applied continuous current this explains why you got the "overpressurising" event. According to this description, you should be able to toggle your rigged-up external power source on and off to keep your fuel rail pressure in the 'happy' band. This probably isn't doing your brand new pump any good, but tell me... can you see the rail pressure responding to your 'toggling', if that makes sense? This could help identify a rail pressure sensor issue.

Silly question... Is ET showing cranking speed while engine is cranking? See if you can verify both crankshaft AND camshaft speed sensor signals. While your in ET, spend 5 mins and check there's no crazy parameters for....



Troubleshooting these really sucks. There's nearly always guesswork involved since specifications seem to be highly classified due to emissions regulations... which leads me to think replacing the fuel rail is the better option (gives you a new rail pressure sensor and discharge valve, and is cheaper than an ECM). The fact that it runs when you apply external power is promising... could possibly rule out debris blocking your injectors if anything.

I guess at this stage we're looking for any reason why the ECM would NOT command the fuel pump to 'pump'.

hvguy said:

im a little confused as to why they have 2 pins dedicated for ground and signal for the pump.

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Nige said:

The boost pressure sensor and cam position sensor shown on your snip are both PWM sensors. They require an external power source (+5v) that is supplied by the ECM and a ground back to the ECM. The output signal from the sensor, also to the ECM, goes not surprisingly via the signal wire. However neither of those aforementioned sensors has anything directly to do with the signal from the ECM to the supply pump which is only via 2 wires.

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I'm confused too, but I'm sure there's some kind of logic involved. Before replacing the ECM I'd consider running some new wires externally. That would mean running four wires from the ECM and two wires to the pump, then joining them as per the schematic you modified and attached earlier. That would also involve running a new X985-E117 OR-20 wire to the pressure relief valve.

One more thing, your prime pump sounds good ticking away in your first video, has the sound changed? Hate for this to be something so simple. These have been problems for years.

Chrisso said:

The Systems Operation for your Tier4 final/Euro IV fuel system states:

The valve is opened and closed by the ON/OFF of energizing the PCV [Pre-stroke Control Valve - fancy way of describing the fuel pump controller], which is controlled by the Engine ECM. The ON/OFF timing is controlled based on signals from various sensors to provide optimal rail pressure.

If you applied continuous current this explains why you got the "overpressurising" event. According to this description, you should be able to toggle your rigged-up external power source on and off to keep your fuel rail pressure in the 'happy' band. This probably isn't doing your brand new pump any good, but tell me... can you see the rail pressure responding to your 'toggling', if that makes sense? This could help identify a rail pressure sensor issue.

Silly question... Is ET showing cranking speed while engine is cranking? See if you can verify both crankshaft AND camshaft speed sensor signals. While your in ET, spend 5 mins and check there's no crazy parameters for....

View attachment 246970

Troubleshooting these really sucks. There's nearly always guesswork involved since specifications seem to be highly classified due to emissions regulations... which leads me to think replacing the fuel rail is the better option (gives you a new rail pressure sensor and discharge valve, and is cheaper than an ECM). The fact that it runs when you apply external power is promising... could possibly rule out debris blocking your injectors if anything.

I guess at this stage we're looking for any reason why the ECM would NOT command the fuel pump to 'pump'.

Click to expand...

UPDATE
I took the whole machine down to the main cat store in houston to borrow one of their good ECM's for testing. Unfortunately this didnt help at all. It still didnt run. I no longer have the machine in my posession however i will hopefully have some updated info in the next week. Ill keep yall updated.

@Chrisso Yes the pump was in good shape, I actually replaced it at the beginning of this year which lead me to find there is some junk in my tank that was clogging the fuel inlet hose. I blew it out with my truck air and kept on running. You can actually hear the change in the pumping noise when its getting clogged. And I verified about 5psi @ maybe 3gpm being supplied to the main HPFP.

No worries hvguy. Looking forward to the update... very keen to know what they find.

Ok, so the dealer said since I installed the pump out of time it messed it up... I don't believe this seeing as out of time wouldn't matter since it just wouldn't inject fuel.

The way this injection system works is the pump works like an old element style pump, except instead of having a spiral spill port, that uses a solenoid to reduce flow by diverting the excess to the return port.

They said I would have to replace my brand new pump with a brand new pump and it was going to be like $5,600, of which I don't have that much money. I opted to have them put it back together, I replaced the solenoid on the top that looked melted from earlier when I put too much power on it for too long, the machine now starts but it instantly dies.

There are no codes, it builds fuel rail pressure, runs and instantly dies.

I installed the old solenoid that was burned up and it works the same. Also while they were in there they installed a new product link antenna and harness, when I log into cat ET, I can see the product link but nothing is saved in it, no serial, no model no nothing.

What is y'all's opinion.

https://youtube.com/shorts/ShzhNTDutl0?feature=share

hvguy said:

Gonna dig through the service manual.

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Do you have the right service manual for your machine? UENR0129 is what you should be using. States timing procedure and...

Note: If a new supply pump is installed, a "Fuel Pump Calibration Override" must be performed using CAT Refer to Troubleshooting, UENR3423, "CAT ET Service Features, Fuel Pump Calibration".

I'm still trying to work out why that pump is timed and if out-of-timing alone could damage the pump.

Chrisso said:

Do you have the right service manual for your machine? UENR0129 is what you should be using. States timing procedure and...

Note: If a new supply pump is installed, a "Fuel Pump Calibration Override" must be performed using CAT Refer to Troubleshooting, UENR3423, "CAT ET Service Features, Fuel Pump Calibration".

I'm still trying to work out why that pump is timed and if out-of-timing alone could damage the pump.

Click to expand...

Interesting find. I do have the manual for it but didn't see that part. Wonder if they did that

Wow. What a mess.

So when I originally dropped the machine off, I told them it had a new pump but I didn't time it. They instantly pulled my new pump and replaced it with a used but known good working pump in time. The called and said it needed a new pump; something about since I did set the timing it messed it up. I declined and wanted it put back together with my pump but set the timing.

A week goes by and they call with it ready. I get there and the battery is dead? Whatever, hauled it home, charged it up and now it'll start but instantly die.... I spoke with a few other shops and figured it was worth the warranty to just get the machine fixed by cat.

Fast-forward 3 weeks and they call me on a Wednesday saying it should be done that day. I don't receive any more calls until the next Monday saying they had an issue with the new pump.... It would start and then die yeah.... That's what it was doing when I dropped it off.

Whatever. I drive down there to pick it up, had a little talk with the technician who did the replacement and he said the timing was 2 teeth off from whoever worked on it last (cat) so either 1. They fucked up and it was just an accident or 2. They sabotaged the timing to make me come back.

Idk, either way I had a brand new pump I paid for sitting here. So it was shipped off to be tested and came back working.

I asked them for a refund because they have been lying to me this whole time of which they declined.... So now they get to talk with visa.

What an absolute disaster.

For those who care, this is how that pump operates.

It's setup like an old fashioned single element injection pump (imagine a p7100, but no spill port) the pump absolutely has to be in time with the crank and cam since it uses those 2 positions to control the electronic spill port on the pump to regulate pressure. It's pretty clever but also pretty dumb since they're the only ones that use this proprietary pump. If you check bobcat and Kubota v3800 engines. They also use something else. It's weird.

Sorry to hear, sounds like a disaster alright.

hvguy said:

the pump absolutely has to be in time with the crank and cam since it uses those 2 positions to control the electronic spill port on the pump to regulate pressure

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Mind if I ask how you know this?

Since your post about pump timing first came up I've been asking around too. A knowledgeable person explained to me that it has to do with controlling the "pulsing" and "pressure spikes" created by the high pressure fuel pump (30,000-odd psi). We're talking many fractions of a second but the goal is to make sure the spill port (in this case the Pre-stroke Control Valve) doesn't open at the exact moment an injector is injecting. This helps regulate combustion and keeps the penguins happy.

I get the similarity between this pump and an older mechanical element pump in the fact that it uses an element to control discharge... but these common rail pumps first create pressure using a gerotor style feed pump (Cat calls it a Trochoid pump)...


Once you get the high pressure created by the feed pump... the rest is up to the Pre-stroke Control Valve to simply control the amount of discharging...



So the more I think about it, I can't really agree that it's anything like an older element style pump. Maybe someone more knowledgeable here can prove me wrong? Anyways, good discussion.

Before anyone comments, yes I know you can't have pressure without a restriction. I could've explained that a little better, but hope you get my drift.

My main interest in this is trying to work out exactly HOW the engine ECM knows the pump timing is out (and thus shuts engine down after a second or two).

This would go along way to proving the dealer wrong and you disputing the bill (or at least part of).