no start when cold

[Cam]

My car will not start when its cold out. I replaced the cts recently, and am going to check it with an ohm-meter when I get off work. I expect it to be good. She runs fine when warm out, fuel pump is new, regulator tested ok, and she runs fine when the ambient temperature outside is above say 50 degrees F.

Any ideas guys?

[svxfiles]

Originally Posted by Cam

Any ideas guys?

Girls are hard to understand.

[Cam]

Originally Posted by svxfiles

Girls are hard to understand.

Your telling me. Luckily I can do a resistance test to check the coolant temperature sensor. I am going to install my fuel pressure gauge so that I can monitor what is going on with the fuel when its cold out.I wish j could permanently install it but that just wont work with the kit I have. Anyone have a good link to a reliable gauge that can be permanently installed between the filter and fuel rail?

[Cam]

Tested the coolant temperature sensor. 2.2Kohms when at room temperature. Perfectly within spec...I suppose I will install that fuel pressure gauge tonight if the weather gets a little better.

From what I have been told (on good authority) the fuel pressure regulator is a vacuum diaphram. If it is able to hold vacuum without leaking, IT IS GOOD. This is the case with mine, so I suppose I can rule that out. Fuel pump is now brand new and functioning flawlessly. Car started when I got home today, but not this morning. It is a clear pattern. Cold weather = no start.

What all can cause this? Could the pump relay be affected by the cold weather? That would explain why it stalled last monday I suppose. I am not going to go digging any more tonight unless the weather gets bettery, and quickly.

I am starting to lose patience (something I have quite a bit of normally). But, daily problems with a car are definately frustrating.

Any suggestions or input? (besides install a fuel pressure gauge )

[Cam]

I FIGURED IT OUT!

So, this morning I went to attempt and start my car. I noticed that it would not illuminate the check engine light again. So I unplugged the fuel pump resistor. Still not CEL. I plugged the FPR back in, and began brainstorming.

To make a long story short, I got a little frustrated and hit the ECU "gently". POP. CEL came on, and then went off again. I grabbed a wire bundle (far driver side) and began moving it back and forth, and the CEL would come on/go off as I did so. I unplugged the connector, and plugged it back in.

No problems so far. I am going to take the ECU out and inspect the board and make sure that all the contacts are good and there are no broken components. But that was definately my problem.

Not sure why it mostly did this when it was cold outside, but it very well could have been coincidence.

BTW, my rough idle still exists. Still not sure what to think about that. I am going to get the A/C charged and see if it runs better in fast idle.

[icingdeath88]

Cold = wires shrink and retract, pulling the iffy contact apart. Warms up and comes back together.

[Cam]

Okay, so the no start when cold has turned to no start. New symptoms are flashing CEL. Not like it's throwing a code, but it is clicking on and off. All the relays in the fuse box are clicking on and off as well. Logic tells me this is a power issue. I have cleaned all the contacts in an attempt to fix this, but it didn't work.

It look's like I have to replace the leads and grounds in the engine bay. Good thing I bought all that stuff for the wiring upgrade. Unfortunately, the car is sitting at work (it got me there on monday, but wouldn't let me leave ).

I haven't had my multimeter with me either to check continuity. I suppose I will grab some jumper cables so that I can jump the block ground to the battery, and at least rule that out.

[XT6Wagon]

mine did this and I think it was a loose body ground. I didn't have the bolt quite tight as the corrosion on the threads of the hole made it a stiff turn with a wrench long before it snugged the wire down.

I haven't looked at a FSM recently, but my SVX seemed to have *0* engine to body ground wires, which means the body is barely grounded at all with that single corrosion prone wire next to the battery. So I added one between the intake manifold and a bolt holding down the A/C drier. Dunno if anything there is making electrical connection, but I atleast feel better. I really need to get the right terminal connectors so I can do a proper "grounding kit" for it since it clearly needs more clean grounds than I bought it with.