Since I spent the last couple of years bringing the beast up to snuff she runs beautifully and is a joy to drive. However, yesterday I drove it about 10 miles to my destination and was there for approximately 45 mins. When I went to start it, it didn't fire up as usual, and I had to press the accelerator for it to start and hold it for bit for it to settle down and idle properly. When I got home, I shut it down and restarted to see if it would repeat, but it started without incident.

I've got new coils, new harnesses, refurbed injectors/rail, new plugs, new leads, TPS adjusted, throttle body cleaned, butterflies at spec, no loose linkages, etc. as the Wizard of the Southern Cross commands.

Searching the archives I found someone who reported similar and replaced the coolant sensor which resolved the problem, does that makes sense? Or would be something else?

Thanks for your input!

 

Maybe she had a few drinks too many, and needed a little pounding on the pedal. Maybe less drinks are the least fun option.

 

New coolant sensor very good idea. It could have been that.

 

MMMMMM,

For $20, well worth it, and check the integrity of the wires inside the plug and the boot, they are known to get corroded in there, and reek general havoc.

The EFI Resistor Pack, RH front corner of the engine bay. You may have addressed the grubby plug and socket in your refurbishment, but again, worth a 2nd look, as they DO reek havoc due to crud on the terminals.

Then it gets technical. Voltmeter probed into the WHITE wire at the +ve terminal of a coil, and go for crank, and watch the voltage drop, hopefully no more than 1V. If it is more, come back, a relay for that White wire fixes that for our lifetime.

 

Can it be swapped without having to re-bleed the system (assuming it's done on a cold engine)?

Thanks

 

Yes. Maybe not officially, but coolant doesn't come pouring out.

 

Suggestion that has worked well for me.

Cold engine, you said that, release the tank cap, refit tank cap, change the CTS.

You MIGHT get a dribble, but that is not enough to rebleed that I have had.

The only reason I release and refit the pressure cap is that some cars hold a residual pressure, very small pressure, in the system. 2 of mine did not, 1 did.
If there is any pressure in there, coolant will flow more than you want and rebleed will need to be done.
The refitting of the cap creates a SMALL Vac in the system.

Have the new one ready to go, old out, new in, 2 seconds tops. Tighten the new at your leisure.

 

Grant, could you elaborate on the relay for the white wire comment? I'd love to hear about ways to get a better 12v to the coils.

 

Grant's fix involves using a relay to get a better voltage to the coil. He advised me to do this, which I did, and it certainly helps starting.
On the coil positive terminal is a white wire. This carries the 12v to the coil from the ignition switch. The current has to go through the switch to get to the coil. This is the procedure:

• you fit a relay in the engine bay, and use the coil white wire as the trigger for the relay,
• earth (ground) the other trigger terminal
• take a 12v feed directly from the firewall post to the power side of the relay; use a very well insulated thick guage wire for this and ensure it is properly and safely routed and cannot chafe etc etc.
• take a wire from the switched power side of the relay to the coil positive.

Then, when you switch on the ignition, the ignition feed switches the relay 12 volt power to the coil directly from the 12 volt firewall post. Using a fused relay is a good plan with a 15 amp fuse; Then, when cranking, the coil is assured of a decent 12 volts. Grant has found that the standard wiring often produces a reduced voltage to the coil during cranking.

 

Thanks Greg.

I located my relay under the dash, but I was 20 years younger, and 100% **** about electrical items being in the engine bay, having spent 3 weeks removing a bucket load of electrical gizmo's OUT of the engine bay.

BUT, doing that now, under the bonnet, as me getting under any dash is purely a dream.

Same procedure:

Locate the White wire from the Ign switch, just on the chassis side of the multi pin plug, cut that wire.
The White cut wire FROM the switch attaches to terminal 85 of the relay.
The White cut wire going forward attaches to 87 terminal of the relay.
12V HOT from any Brown wire attaches to terminal 30/51 of the relay.
A NEW Black wire, from terminal 86 of the relay to EARTH.

Also did the Accessory wire (White/Pink), and that livened up a hell of a lot of things in the whole car. Think about what comes alive in the Access (Pos 1 to some) position in your car, Stereo, Climate system/fans etc etc. They could ALL do with a cleaner 12V signal me thinks,

 

What year is the car? My 91 would do the same thing until I replaced the check valve in the fuel line. Engine heat would vaporize the gas, causing vapor lock. This was due to the pressure in the line dropping due to the leaky valve.

 

It's a '90 which is functionally identical to the '91. After replacing the coolant sensor, I repeated the same conditions and it started without incident. However, if it happens again, I'll look to the check valve.

Thanks