For the first time I was a victim of driving down the freeway and having the car stall out. Then towed to my garage. Car will crank though not start. Spark is in question. No codes came up.

I have been noticing a problem re-starting the car after a certain time. Starting and stopping back to back wasn't a problem, or first thing in the am. After the car sat for a few hours it would struggle to start. Hesitated and started with a low rumble then up to idle vs. ignition to right to idle. (if that makes sense)

I wasn't too sure what to diagnose. Coils & Plugs are all new. My first first thought was maybe the starter then after it died I thought it was the fuel pump. (wrong assumption as I can hear it starting up in the trunk) I have moved a whole bunch of Relay's around, though still no luck.

What I did find was a burnt fuse for the intercooler water pump. Which explains my last post of why i thought the cat was running hotter than normal. (what I thought was too hot, though never over 200F)

I have searched high & low looking at a few threads and my problem seems to lie with not having adequate spark. (one suggestion was to get a phonebook and call cause it could be major) My guess was that perhaps the heat has cooked one or some of the coils.

I pulled a few out to see if it would spark. Long story short, I didn't see any spark from cyl 2 then when i moved both plug & coil to cyl 6 the same coil & plug sparked. After taking out cyl 2,4,6 all together I noticed they did all have a faint spark, I put them back in but with no luck. The battery was low on juice so I am going to re-try in the am. (charging the battery while disconnected to clear any history)

My wild guess is the ECM. I have heard of Cylinder wash from cranking it too much, or a key exciter??

Really am stumped, I was ready to put in a fuel pump.
Any advice is greatly appreciated.

 

My wild guess is that you have lost your fuel pumps.

The fuel system does not have any OBD II codes associated with pressure but it is easy to check. Test with a pressure gauge at the Schrader valve on the fuel rail.

 

Is your car a 4.2L?

If so you can check the fuel pressure on your OBDII scanner if it has real time monitoring.

I am suspicious of the no spark diagnosis, as these cars are quite sensitive at detecting misfires and setting approriate codes.

 

No such luck with a full battery (I wasn't expecting much)

It is a 4.2, though my scanner doesn't have the capability to read pressure.
(Does the 4.2 only have one pump? I called my dealer and they want $980)

I have read that when you have the plugs out after cranking it, you should be able to smell gas on or near where the plug goes in. Which I can clearly smell gas. That and because I can here the pump should rule out the pump, shouldn't it?

I have noticed the Schrader valve on the driver side fuel rail closer to the front. Is there also one on the passenger side?

After sleeping on it, I am wondering about the injectors. The only reason I guess is because I would sometimes notice a rattle or chatter when under load. I researched that a can of bg44k might help (detonation), and it did. I went through 3 cans and the noise was minimal.

If the fuel pressure is good, How can I test the injectors (beside taking them out, if at all possible)

Thanks

 

The injectors are not all going to fail at the same time and you can't test them without removing them and then only if you have a test setup.

There is only one Schrader valve. Call around to your local auto parts stores and see if anyone will 'rent' you a fuel pressure gauge.

Anything else would have surly set some kind of code.

 

I had to buy a fuel pressure gauge. It seams it is the pump.
I just want to be sure, I don't have any pressure when the car is cranking, or when the key is in the on position. I screwed the gauge onto the Schrader valve, I hope there isn't some complex method?

Feels odd, as I am sure I can hear the pump turning on. Is there any way / other test to check the pump just to be sure?

Is replacing the pump harder than taking out out the Supercharger? & can anyone recommend a good place to buy the pump. (In Canada or reasonable shipping)

THANKS for all the advice.

 

There were a couple of instances where the hose came off in the tank. The pump would run but no fuel. I believe there is a DIY on removing the tank, also several threads with good instructions.

 

There is also a fuel pressure sensor in the 4.2 model that controls the pump pressure. This sensor is up in the fuel rail area. If this is bad, it could signal the pump to lower pressure. I suggest gettting a diagnosis by a pro. These pumps and sensors cost a lot more than a diagnosis.