engine gets hot... engine dies

[rlux4]

Me too. I have a tank out now on a 31' motorhome to clean it, change the pump, and clear the lines. 47 gallon tank that was 3/4 full of 10 year old gas.

Ron

[davery]

Could there be anything in the tank? After the engine is on a while it gradually gets into the pump and stops the the flow. After you stop, it floats back into the tank only to have the same thing happen again.

[81SPIDERMATT]

ok first let me apologize... my original information may not have been correct..... twice today i drove to breakdown.... meter readings from fuel pump ... at start up 13.5.... it varied a bit when turning on headlights and fan... would drop to just over 12 with other stuff on.... would get as high as 13.7 without stuff on.... at breakdown it never changed... when cranking and car not starting same just over 13 volts

now the fuel was present both times today and although it sputtered a bit when cranking it was only for a short bit before steady stream off fuel.... at breakdown cracked gas cap and no change and no sucking sound

electrical is a different story.... once again i am sorry... i did not take the advise of bringing some type of shade the first time... i did not make that mistake again... checked it in the sunshine outside (with a pink umbrella..go ahead and laugh) before and got consistent and what i would call good spark....now at breakdown when it sparked it seams weak and was not consistent at all... sometimes 2 full seconds would pass with no spark

and i am not going to say anything about heat

[So Cal Mark]

have you replaced the ignition module? checked voltage from the ign switch to the coil?

[81SPIDERMATT]

have you replaced the ignition module? checked voltage from the ign switch to the coil?

nothing ignition has been replaced.except plugs and wires.. should i get one .. or are you just asking

i will research how to check voltage from switch to coil..... unless you can point me in that direction.... pictures help me a lot

and when i figure it out... is this something i should do at home and then at breakdown to see if there is a difference?

[majicwrench]

Now while at home, take test light and hook it to (-) side of coil. Crank engine. LIght should flash. THis is the module grounding the circuit thru coil.
Now drive. When dead, once again verify why it is dead, spark or fuel. Now, Check see if coil (-) still flashing. Verify again no spark at plugs.
YOu may also be able to use your tach for this same test. At home, remove coil wire from dist and ground. Now crank engine. SHould see tach needle bouncing up. When dead, try this again, see if needle is not moving.

The ignition module in the dist is an item that can, and will, fail as it warms up.
Keith

[81SPIDERMATT]

ok will do thanks.... monday is out... will post results on tues as soon as i have them..... Matt

[81SPIDERMATT]

have not driven the car again... getting ready for family reunion trip has taken all my time... please dont give up on me... i will be back 2nd week of july...... i cant do it without you

questions

can i hook up the meter to the coil like i did on the fuel pump to get constant readings? i will also do the test light
should i buy a fuel pressure thing so i can give accurate readings about the fuel .. as to eliminate that for sure?

i know the tests we are doing are pointing to some area of failure ... got a short list of what you think it might be??

been looking at replacement costs of certain things... got my fingers crossed for that 30 dollar ignition module

thanks.. and i mean really really thank you......... Matt

[FulviaHF]

The symptoms you describe initially made me think it was electric/electronic. I stayed out of this as it then seemed to be coolant or fuel, but I have seen intermittent heat failure of a coil more than once. Everything's fine until it gets hot, then it cuts all spark. If you've never replaced the coil, I'd consider trying that. If not that, then it's possible the ignition module or one of the relays is shutting down in heat failure. But I'd always guess coil first.

I could be way off base here, but that's what your initial description of the symptoms sounded like to me. And eliminating coolant and fuel has only reinforces it.

[81SPIDERMATT]

bumping up for a question

going tomorrow to pick up some type of fuel pressure gauge... can i put it on the cold start fuel line to get an accurate reading at breakdown? should i hook it up after car is running? ...tips appreciated

besides the test light test before and after would hooking up a volt meter to the b- side of the coil for a constant reading help in any way... thanks... Matt

[rlux4]

Yes, connect the fuel gauge to the line going up to the cold start valve. The engine doesn't need to be running for the fuel pump to operate if you turn the key on and open the flap in the AFM by hand. To give you an idea of what you'll need, here's the fuel gauge I rigged up to use.

You can see the barbed nipple I put on the end of the black tubing that goes into the cold start line. The clear tubing is for releasing the pressure when you're done.
Ron

[majicwrench]

At this point I would not spring for a FP gauge but that is up to you. Yes, with some messing with the pieces you can tap into CS inj line. For that matter you could hook it up (engine warm) and drive it that way with gauge on windshield. But you need to find out FOR SURE if you are loosing spark, or fuel. On the coil, #1, coils almost never fail, very simple devises. #2 a digital volt meter is not best tool for watching neg term flash as engine being cranked, meter won't update fast enough. Like I said earlier, at home,, everthing working, remove coil wire from dist, ground to something, now crank engine and watch tach, it probably bounces around. If it does, that is good, no need to rig test light. But if you have to, with coil wire still grounded, get test lite, you may have to rig some alligator clips here, but arrange it so you can see it from Drivers seat, and hook it to neg terminal. Now crank engine, you should see lite flash. This is the module grounding and opening the coil to produce spark. If, when engine dies, tach is not bouncing and/or test lite not flashing, you know ignition is failing, no need to go any further. Now crack fuel line at CS so you know how much fuel when everythign working. Now drive it till dead AND CHECK THESE THINGS AGAIN.
Short list, not going there, you need to test and see what is failing.
Keith

[81SPIDERMATT]

ok.....

test light same as before and after breakdown

spark is same ... at first i thought it was weaker but it was just slower... at cold start it goes slow until engine catches and it starts then spark gets faster... makes sense... at breakdown spark is slow but never gets faster because the engine never starts and speeds up spark... now i see why i thought it was weak... makes sense

autozone rented me a fuel pressure test kit....

at cold start 30ish to 38 when accelerating.... while driving quick response on fuel gauge to 38 ... as car got warm fuel pressure begins to jump up and down when keeping constant speed... between 32 and 28.... as car starts showing signs of near breakdown (try to accelerate and bogs down) pressure gauage instead of going up to 38 drops to as low as 20;;; this continues until car dies.... right before it dies as you push on gas pressure just keeps dropping to around 10... at this point if i stop and let car idle it may hold idle for a minute maybe.... any attempt at foward movement drops pressure even more ... once below 10 it just dies.... voltage meter on pump shows constant votage thru all of it from between 13 to 13.7... never does the voltage mimmick the pressure gauge as i would have thought it might...... 5 minutes under a shady tree and when first try to start no ppressure for several seconds... then slowly starts to climb as i am cranking motor... when it gets to about 25 car starts.... runs like crap ... same as near breakdown... if i let it cool longer... or sit longer.. might not be heat... it runs great

sat i ran several errands and no symptoms.. but they were short runs... its the longer driving... know i am not supposed to say it but seems like it happens when its good and hot

looks like i have 2 fuel filters... one right before the pump and one after....

awaiting instructions oh wise ones.....

[81SPIDERMATT]

was just reading back a bit.... i had everything hooked up when i did the test light.... flashes pretty fast both times... i did not unhook coil to dist wire and ground.... thought that was a seperate test.and when i did that test.i coulld never get the tach to jump as you spoke of... very little jumps maybe but nothing past that

[So Cal Mark]

your car wasn't intended to have a filter before the pump. There should be a screen on the pickup tube in the tank for that purpose. Those electric pumps don't suck very well, but they make great pressure