i'm sorry. and don't laugh. but you guys are so dedicated that i decided to post my mom's '91 buick rivieria engine problem at a ford trucks forum.

here's what i know. it's a 3.8 engine. after the engine warms up or gets hot, after about 10-15 minutes, the engine shuts down completely. no warning...no chugging...no over-heating. engine just stops and power steering goes out...power brakes go out everything. she waits 15 minutes and can start the engine again.

all suggestions, advice, and opinions are appreciated.

 

c'mon...anyone?

shelly

 

Start by determining if it has no spark or no fuel when the problem occurs. You need to begin to narrow it down a bit.

 

could be the crank shaft senser, get a haynes manual and a paper clip and check the codes.

 

no spark. and pardon me if i'm not that clear...(i grew up playing with dolls, not trucks).

my dad says he's getting fuel. he loosened something and pressed down and fuel comes out. he said when he does something with 3 coils, he's getting no spark. he replaced the cam sensor and that didn't fix it. i suggested he go to murray's and get the machine to read the codes (it's free, just leave a deposit).

where would one get that haynes manual? is that similar to a chilton's manual?

 

"where would one get that haynes manual? is that similar to a chilton's manual?"
yep.

"he loosened something and pressed down and fuel comes out"
fuel pressure port, it has a shrader (sp?) valve like a tire and a screw on cap like a tire.


"he said when he does something with 3 coils"
that would be the coil pack.

"he's getting no spark."
bad crank shaft sensor can cause that.

"he replaced the cam sensor and that didn't fix it"
doesn't need the cam sensor to run,

most likely causes,
1) crank shaft sensor ($20)
2) ignition thingy under the coils. (aint cheap)

the cam sensor goes in to the timing cover just below the water pump.

the crank sensor uses a small bracket to hold it and it reads a wheel on the balancer.
look down between the crank and A/C compressor, you will see the bracket and some wires.

 

Have you changed the fuel filter lately?

 

i told my dad to go get his ecm tested at the local murrays auto parts store. he will probably do that saturday afternoon.

will an ignition module tester identify whether it is the crank shaft sensor or the ignition thingy or the fuel filter specifically?

 

sounds like a faulty coolant temperature sensor... you'll have to watch the gauges too, see if the temp gauge spikes just before shut down.

a no spark situation can be the crank sensor, if its got one... but you'll be able to tell, because it'll throw a code...

good luck, and post the results...

 

Take it to a garage, let them run a diagnostic on it.
Be sure to tell them (in detail) what the problem is.

It 'could be' a lot of things, . . . . or not!

 

Both the Ford and Chevy TFI systems are know for the modules dying when they get hot. The Chevy is also known for EPROM failures for absolutely no reason. Which leads to a no spark condition too.

 

okay...can't rent the scanner to read the codes cuz they were all rented out in the tri-county area. so i used the paperclip method. the code is 17 which narrowed it down to 3 possibilities.

1. RPM signal problem 2. Camshaft sensor - circuit problems 3. Electronic Control Module (ECM) computer circuit problem - Pull-up resistor (Saturn).

i think we found the crankshaft sensor but we couldn't remove the bracket around it. the part is only 24.99 so he'll pick that up tomorrow along with a scanner if there are any available.

but, need some clarification. the cam sensor he already replaced. the crankshaft sensor would be a code 18. what exactly is the camshaft sensor? this is a third sensor? or is the gm code guide using a term interchangeably?

any info regarding the correct location of the crankshaft sensor is also appreciated. my parents are both in their 60's and on a limited income. that's why they don't take it to a shop right away.

thanks in advance.

 

That would be both the cam and crank sensors... you can get an ECM from a junkyard for about $25.

 

In a four stroke engine, the crank turns two times for every one turn of the camshaft. The crankshaft sensor by itself cannot identify when cylinder #1 is at TDC (top dead center) which is needed for engine spark timing; the cam position sensor does this.

 

"i think we found the crankshaft sensor but we couldn't remove the bracket around it. the part is only 24.99 so he'll pick that up tomorrow along with a scanner if there are any available."

The crank sensor comes with a new bracket.( They break easily, trust me i know) Make real sure you get the new one lined up right or you will be buying another one soon.

dads '89 has a problem reading the cam sensor (ECM says it ain't there) it runs ok with out it, just a little stumble from idle if you jump on it.