Fuel pump questions

Ok, so as most of you know, Mikes engine is blown. Atleast we think. The compression is 135, 130, 130, and 130, and we figured the reason it quit running is the compression became too low. Well, after reading that one guys post on his fuel pump, I suddenly had an idea of that maybe being Mikes problem. It would suck if it was, we could have had the beast running a month or two ago, but I suddenly doubt his car running after a rebuild. I remember someone on here saying their compression was much lower than that but it was still running, so I want to check a few things before we go through with this. So in that guys thread, he said he couldnt hear the fuel pump going then the key was in the "on" position. What will it sound like and will it always turn on? We disconnected the fuel line from the fuel pressure regulator (black cylinder on firewall is it correct?), fuel should come out of the top when the pump is turned on right? I am thinking we are going to check the pump before we do any more engine removal. Correct me if I am wrong:
- If it comes on when the key is in the on position but it doesnt start, the fuel pump is ok and its something else.
- If it doesnt come on when the key is in the on position, but it does when hooked up directly to a battery, the fuel pump is ok, its the ECU or the fuel pump relay.
- If it doesnt come on with the direct connections or the key, its bad.
If those statements are correct, I am going to test his fuel pump before the engine gets out. How can I test the ECU? Hes got quite a bit saved up so we can replace some parts with aftermarket ones. I'm smelling DSM link soon. I doubt that the injectors all failed at once and he has been using the injector cleaner, so they shouldnt be clogged. I really hope we can get this figured out for sure and get the beast running without having to rebuild. Its kinda hard right now seeing as how it was -55 to -75 with the wind chill last week.

Also, I made my own thread on this because I didnt want to jack his.

Like I said in the other thread, if the car is off the pump only comes on when the key is in the cranking position so you could just disable the starter and do it that way, unless I'm crazy and they only did it that way in talons, but I guess mikes is a talon to lol. Anyway as far as the ecu, open it up and look at it and see if you can see/smell anything burnt I'm not sure the specifics of testing that.

No the pump comes on when the key is in the "on" position. And yes all your facts are right, but I would check the relay before the ecu, and I doubt only the FP would stop working if part of the ecu fried.

No the pump comes on when the key is in the "on" position.
IDK about an eclipse but I know for a fact it doesn't until its cranking in a talon. my starter went out and I tested that theory, its also very common among Chrysler cars

The fuel pump comes on when the key is in the on position. You can hear it very clearly. I'd say check the fp out, also does he have a fairly new fuel filter? It would have to be pretty clogged but it's possible. The car should run with that compression.

Well then I guess they did it differently in eclipses and talons
EDIT: Got to thinking about it and realized that because it would only turn on for a short time I probably just never noticed it until my starter went out when its on constantly while cranking. But 75%+ of all Chrysler products don't turn the pump on until you crank the motor. I apologize for the confusion

Well then I guess they did it differently in eclipses and talons
LOL, you should know better!! They are the exact same!!! The fuel pump comes on with the ignition on. Believe me i have both and they both do it. Maybe you just can't hear your's but it is on.

LOL, you should know better!! They are the exact same!!! The fuel pump comes on with the ignition on. Believe me i have both and they both do it. Maybe you just can't hear your's but it is on.
Hence the edit. Give me a break, I'm going on 12 hours of sleep since sunday :lol: I'm a little out of it

Sorry you must have edited it while I was posting.

On the turbo cars the pump does not come on until the ECU sees a signal from the cam angle sensor. To prove this, remove the CAS and turn it by hand with the key in the on position. You will hear the injectors or spark plugs click, and the pump will come on. You'll be able to hear it clearly with the motor quiet. This is how I diagnose bad cam angle sensors :)

Thanks for the help guys. We are going to test the pump and check the filter some time soon. We're thinking this will maybe explain the knock too, maybe the pump or filter was failing and wasnt getting enough fuel to the engine causing the predetonation. Thoughts or ideas? Does that sound right?

predetonation(preignition) and knock are two different things. If you heard it, it was knocking(detonation)

Oh, I though knock, detonation, and predetonation were all the same thing. Whatever you want to call it, his spark plugs barely made it a month before they melted all to fuck. Also his manifold was cracked in no less than 3 separate spots. That leads me to believe he was leaning out causing the excessive temperatures which melted the spark plugs and caused manifold to crack over time. Thats knock/detonation correct? The pump/filter were not providing sufficient amounts of fuel causing the higher air to fuel ratio and thus he was leaning out and knocking. Does my train of thought make sense to anyone else or am I crazy?

EDIT #2: Also, seeing as how the compression is basically the same through out, the 3 cracks are all over the manifold not just on one side, and all the spark plugs were showing similar melting, I am led to believe it is not a clogged injector or something like that.

EDIT: Good to see you again Kevin!

You hit the nail on the head. Technically speaking its more like he was leaning out which caused higher cylinder temps which in turn created a hot spot and consequently caused detonation, but your definition works just as well lol

I still say that anyone that car hear knock in our cars should be renting thier ears to NASA or something. Unless you fags are all still running stock exhausts and airboxes :D

Unless you fags are all still running stock exhausts and airboxes :D
Little harsh are we:lol:

Yeah, no shit! I shed a tear because of that Kevin.... *sniffle sniffle* ;)
Remember the Nymore custom intake and basketball hoop pole test pipe mated to a megan DP and cat back?

Just an update guys, we checked the fuel pump today, its pumping alright. We are going to put the engine bay back together and start checking other shit. We're going to check the fuel filter, we never thought about that until later... the guy that had it before us didnt exactly take great car of the car.

sounds like you need new injectors :lol:

:lol: Yeah, but I doubt they all shit at the same time. We'll see, but you may very well have a PM in the next few days ;).

You need a flare nut wrench to do the fuel filter, I think it's 14mm but i'm not sure (i have a whole set it comes in handy a lot!!)

Its smart to use a flare nut wrench so you don't have to deal with stripping it out but if you don't have one you could make do if you're careful, I used an impact for the banjo bolt, works real good.