98 S70 Runs for 4 minutes then dies.

steamnjn23 · Post by **steamnjn23** » 30 Dec 2014, 20:57

My car runs for 4 minutes then dies...give it about 20 minutes and it will start up, running 4 minutes then dying again. Years ago with an old Chevrolet, it was the coil that caused this kind of problem. When it dies, I checked the spark with another spark plug and there is no spark at the plug, give it 20 minutes or so and there will be spark and the car will start. Makes me think coil, but a new one didn't solve the problem either.

Listed below are some of the things I have done over the past 3 years I have owned the car, I am offically stumped and I know I am over looking something so help me out.

I have:
replaced the coil, (twice...under warranty)
jumpered the fuel pump relay,
tested and confirmed the in-tank fuel pump,
replaced the coolant temp sensor,
replaced the crank position sensor,
replaced the cam position sensor,
MAP/mass sensor,
replaced vacumn lines,
cleaned PVC system,
changed timing belt and pulley.

Post by **tryingbe** » 30 Dec 2014, 21:41

Any codes? Check plugs and wires?

Rbaratt · Post by **Rbaratt** » 30 Dec 2014, 22:06

Maybe the overload relay. I'll have to check but I think that relay provides power to the coil.

steamnjn23 · Post by **steamnjn23** » 30 Dec 2014, 22:28

New plugs and wires.

where is the overload relay...is it known by another name?

Post by **cn90** » 30 Dec 2014, 23:21

How old is fuel filter?
Spark Plugs? (I use NGK Iridium).
Cap/Rotor: Bosch only.
Bougicord.

ECT: usually the aux fan runs all the time when ECT fails, but does not hurt to check it.

steamnjn23 · Post by **steamnjn23** » 30 Dec 2014, 23:35

fuel filter is new, cap and rotor are 6 months old...bought from autozone, not sure if it is bosch or not.

fan doesn't run continuously, it cycles on and off after a couple minutes.

Post by **jblackburn** » 31 Dec 2014, 07:49

Overload relays are the 3 "J" relays in the main fuse box (the outside shell lifts off with a couple Torx screws).

That...or a bad fusebox to battery cable...would be my inclination as well. Touch that cable after the car shuts off - is it burning hot?

steamnjn23 · Post by **steamnjn23** » 31 Dec 2014, 08:07

My car only has 2 "j" relays. The third socket isn't wired. I swapped around the relays yesterday to no avail. I popped the caps off to look at the relay and didn't notice anything burnt or sticking, no burnt smells either. Is there a way to test the relays other than just swapping them around.

I will check for a hot cable as u suggested.

Rbaratt · Post by **Rbaratt** » 31 Dec 2014, 08:22

I'm not sure if the attachment applies to your year, but on my 850 I believe the overload relay powered fuse 2 which in turn powered the coil (blue/Red wire).

steamnjn23 · Post by **steamnjn23** » 04 Jan 2015, 12:38

My car only has 2 overload relays, while all the pics and descriptions I find show 3 relays. Is this normal?
Is there a way to test or bypass or jumper the overload relay along side the road, similar to the way we do the fuel pump relay?