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Does The Ho Have Coolant Pressure Sensors/switches?


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On the way to school this morning I pressed the gas to accelerate to pass someone on the highway, and my MJ backfired a couple times then shut off. As I was coasting over to the side of the road I started to smell antifreeze. I stop, get out, and there's coolant literally everywhere. All over the engine bay, on top of the hood, on the windsheild, and down both sides of the truck. It took me a long time to figure out where it was came from (no hoses off, all freeze plugs intact...) eventually I fired it back up to see if it would start (it took a while, acting like I'd run out of gas) and discovered that one of the heater hoses had a 3/4" split about an inch above two inches above the water pump, and was spraying onto the rad fan.

 

So my question is, did the truck shut off due to lack of coolant pressure or did the coolant short something out? I'm not blowing white exhaust, there's no coolant in the oil, and there were no warning lights or codes. The truck wasn't even overheating. (if anything it was still cold) I cut the end off the heater hose and clamped it back down, topped up the coolant, and it's running fine now. Should I be looking into this more?

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there is only a temp sensor at the back of the head for the guage, and a coolant temp sensor for the PCM in the thermostat housing ... if you lost the coolant at that point, either something shorted or the PCM saw the colder temp as a result of no flow and flooded the motor out going too rich, ar a hotter temp and leaned it out too much ... the backfiring suggests one or the other?

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there is only a temp sensor at the back of the head for the guage, and a coolant temp sensor for the PCM in the thermostat housing ... if you lost the coolant at that point, either something shorted or the PCM saw the colder temp as a result of no flow and flooded the motor out going too rich, ar a hotter temp and leaned it out too much ... the backfiring suggests one or the other?

Well, it wasn't quite up to temp, it had maybe been running for five minutes when it happened.

 

The split hose probably sprayed slick coolant on the serp belt and caused slippage at the harmonic balancer. Engine trying to rev, belt slipping badly = backfire.

But the serp belt doesn't drive anything crucial to staying running, does it? The engine cut out after running like $#!&, making no power for ten seconds. I suppose the alternator could do some weird stuff when it's stopped suddenly, but that would correct itself and not kill the engine, right?

But there was definitely coolant on the belt... like I said, it was pretty well everywhere. Plus it was still squealing a bit when I got to school, an hour late for a fairly important test.

 

I'm leaning towards a short somewhere... the entire engine bay got a pretty good bath, and there was a cc or so of coolant in most of the spark plug wells. "Topping up" involved almost a gallon. I'd still expect a short that disabled the engine to at least blow a fuse, or even throw a code, but everything checks out... 

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The split hose probably sprayed slick coolant on the serp belt and caused slippage at the harmonic balancer. Engine trying to rev, belt slipping badly = backfire.

But the serp belt doesn't drive anything crucial to staying running, does it? The engine cut out after running like $#!&, making no power for ten seconds. I suppose the alternator could do some weird stuff when it's stopped suddenly, but that would correct itself and not kill the engine, right?

 

My thoughts exactly, are you sure you have your thinkin cap on straight hornbrod?   :hmm:

 

 

 

 

I'm leaning towards a short somewhere... the entire engine bay got a pretty good bath, and there was a cc or so of coolant in most of the spark plug wells. "Topping up" involved almost a gallon. I'd still expect a short that disabled the engine to at least blow a fuse, or even throw a code, but everything checks out... 

 

With all that coolant going everywhere a short would seem to be inevitable and almost without doubt the answer.

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Well, gonna guess that he's pointing out that if the sensor on the Thermostat housing (coincidently, right next to the blown hose) gets messed up in some way (say by a shower iof coolant for example) ... the engine will likely run like poo and stall out? Kinda makes it relevant I 'spose ;)

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Yeah, although whatever it was seems to have fixed itself, or my horking around on things getting that clamp off and then back on again with zero tools fixed it, cause it was running fine when I was done with the fix.

I've also just discovered that the nasty rattle that I've been associating with the exhaust banging around is actually a cracked flexplate. While not likely a cause in and of itself, I can see that messing things up since the cps reads off of it.

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More likely the coolant spewing all over the engine bay FUBAR'd the TPS or the distributor, got everything wet and screwed everything up electronically

 

The computer (ECU,PCM, ECM whatever) does not shut the engine down when it sees cooler temperature...or a lapse in temperature related computer logic.  The TPS does not like getting wet, nor does the distributor.  Just those two things will kill the engine.

 

The coolant sensor "coincidentally" being next to the leak is just that...coincidental.  A messed up coolant sensor is not going to shut the motor down.  A coolant soaked TPS will.

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