1993 940 regina idle and cold start problem

kaiboy760 · Post by **kaiboy760** » 06 Oct 2015, 17:17

I purchased a 940 about a year ago, and over time it has developed a couple problems. First problem was that it would die in the rain. Finally discovered that the hood seal was broken and water was leaking into the distributor cap. So I fixed the seal with silicone and now I have a rough idle. Replaced the cap and rotor since they were rusted from the water. Now it idles at 600 rpm but it is not constant and sometimes drops and the whole car shakes. Not a huge deal but would be nice to have a smooth idle. Also when the car is cold it will not start. It always turns over after about 3 cranks no matter what, but when it's cold it will sound like a dying turkey until it dies about 2 seconds after turning over. Then I will give it another 3 cranks and it will start up perfect. This is my daily driver and I do this every time the car is cold and it always starts up on the second time.

Have replaced:
-spark plugs and wires
-distributor cap and rotor
-coil wire
-crankshaft position sensor

This is my first post on here, thanks in advance if I get any replies

93Regina · Post by **93Regina** » 06 Oct 2015, 21:36

kaiboy760 wrote: Also when the car is cold it will not start.

"Cold" in Oceanside, CA...62°

Rex-I/Regina ignition/fuel system - Ok

Assuming no air induction leaks on intake manifold or injectors' o-rings, the issue may point to the ECT (Engine Coolant Temperature) Sensor. Is it plugged in? Are its plug terminals clean?

Otherwise, check fuel rail pressure...there is a port on fuel rail to check it via Ford pressure tester tool.

Does vehicle have an EGR setup? If so, the EGR maybe by-passing exhaust air if not fully closed.

kaiboy760 · Post by **kaiboy760** » 06 Oct 2015, 22:06

I'm not positive that this is the ect sensor I'm no expert but I think it's the yellow one right?

And does this picture help figure out if I has an egr setup?

Yeah it doesn't get too cold over here I just mean when the engine is cold haha

Sorry for all the questions I'm sorta new to this

93Regina · Post by **93Regina** » 07 Oct 2015, 13:31

kaiboy760 wrote:ect sensor

The yellowish one has a spring clip on it that is pushed in towards the plug itself, and then gently pull upwards. If you can, ground an ohm-meter on engine block, and measure both sides of the ECT. The other plug is for dash's temp gauge.

The other item shown is an Idle Air Control (IAC), and it can be cleaned up internally.

On Rex-I/Regina, the IAC is specific to Regina...a Bosch LH 2.4 IAC will not work.

On Rex-Regina Ignition, there is an air temp gauge; clean it too.

Also: Rex/Regina Coil Pack Contacts Cleaning

kaiboy760 · Post by **kaiboy760** » 07 Oct 2015, 17:06

how would i go about cleaning the air temp gauge?

93Regina · Post by **93Regina** » 07 Oct 2015, 20:06

kaiboy760 wrote:cleaning the air temp gauge?

Electrical contact cleaner: best way to clean electrical contacts

See this PDF Regina Book for ohm specs on ECT and intake air temp sensor

kaiboy760 · Post by **kaiboy760** » 07 Oct 2015, 22:52

Thanks so much for you help! I have just a couple more questions though...

93Regina · Post by **93Regina** » 08 Oct 2015, 12:22

kaiboy760 wrote:couple more questions though...

Throttle Body Port - For emission control...there should be a charcoal canister adjacent to driver's side headlamp, on its rear side. Myself, leave it hooked up, cause it sucks fumes from gas tank. It looks like someone has replaced that hose; mine is just a rubber hose.

Pre-Heat Hose - I would disconnect that silver tube where it inserts into air filter box. If the thermostat is working inside of air filter box, incoming air will be regulated so it is at a set temperature. Problem is, when thermostat fails, engine receives hot air from exhaust header.

Rubber Hose Cracked - That's the high pressure fuel line, but I think the outside part just has a rubber sheathing to protect inner hose.

lummert · Post by **lummert** » 08 Oct 2015, 15:46

Cracked rubber hose has a nylon inner tube.