Cold Start System Testing (hard starting)

[mrnickleye]

I've actually never had a problem with a cold start injector on Toyotas, other than a little dirty. I have had to replace several 'temp/time' switches.
They made some changes in them within the first couple years. All of them, trucks, too. They changed the resistance values to get better performance.

I would do the 'following' testing before doing what the TSRM says.

NOTE: The current is only supplied during the cranking mode, not after the engine starts.

You can test the injector for resistance. per TSRM. 2-4 ohms
http://www.cygnusx1.net/supra/librar...fi/FI_077.html

The TSRM does not go into testing the switch, but you can check some resistance values thru the terminals to see if they are shorted or open.

(I have the specs, I'll post them later when I dig them out)

Also, the switch is heat/cold controlled. If the temp outside is more than about 65* (maybe 55*) it won't allow the injector to come on, to prevent flooding. Also, even in a snow storm, after 12 seconds of cranking time, the switch will stop supplying current to the injector. (prevent flooding)

So...
On a cold vehicle (and you may have to pack a bag of ice around the switch for 10 min. ahead of time), you can pull the injector and place the tip in a jar. Crank the engine to see if gas is spraying. Yes?? then system is working properly.

No spray right away?? Stop cranking, and wait a few minutes for the switch to get cold again from the ice pack. Then hook your 12 volt meter to the injector connector, then crank again to make sure current is flowing to injector. Yes? then injector has problem. Pull it and perform testing per TSRM. No volts? Stop.

Pull connector to time switch and then test for current to it by cranking engine.

Have current?? then switch is likely bad, but check wiring from switch to the injector.

I do it in this backwards order because the overall system gets tested right away. It is actually a very simply design, and seldom has problems.

The switch is very sturdy, and a 'dealer only' part, and is a bit pricey $$$$.

Now....there are other areas to check for a hard start problem. Any codes come up when you scanned it, or check the light by jumping for codes ???

TPS, AFM, coolant temp switch for the ECU. Fuel pressure drop, usually due to a leaking injector, or check valve at the fuel pump (in the tank, bummer).

Feel free to ad your $0.02. Everyone needs 'some' help, shortcuts, and beer.

[adellicson]

I am having trouble with starting my car. I beleive it is the cold start injector, but not that its not working correctly, I beleive it is leaking and causing the car to flood when sitting for a while. The cold start problem worsens the longer the car sits, thats what make me think it is the cold start valve. I suppose it could be loosing fuel pressure while sitting. I asked a friend who is a toyota mechanic and he asked his buddy who has owned a few of these and is still a mechanic for toyota and that is what he thought as well. Tell me what you think. Thanks

[mrnickleye]

You should perform a fuel pressure and leak-down test. If you have a leak, you can easily pull the CSI to see if it is the problem.

[schutz86]

where is the cold start injector located?

[mrnickleye]

Ops. Its on the intake manifold, with a fuel line, and a rectagle connector to it.

[schutz86]

thanks alot.

[Bossard]

I have a Celica with a similar problem: hard starting as soon as it goes down to say 60 degrees or below. I think it is the cold start injector not working because if I spray a small burst of starting fluid into the throttle housing through the butterfly plate it kicks right off. I have a Celica GTS with a 2.2 liter engine. There is a relay block in the engine compartment with a lid with markings. One of the markings says fuel and there is no fuse or connector plugged in where that fuel marking indicates inside. I wonder what this is for. My other Celica has a two pronged copper connector where this one has none on the same engine. Does anyone think that could be the connection for the completed circuit for the cold start injector?

[batmmannn]

Is there a place where I can learn how to apply starter fluid I am not that familiar with fuel injection and don't know where to spray on my MK3 where is this butterfly plate? Thanks so much!

[Bossard]

On my Celica with a 2.2 litre engine I have a rubber hose that connects from the air cleaner to the throttle housing. It is attached on both ends with a hose clamp. If I loosen the hose clamp at the throttle housing and remove the hose you can see the butterfly plate inside. You can rotate it open to spray starting fluid internally. Also, you can just spray starting fluid into the air cleaner as this will drawl into the throttle as well. Just give a quick short spray though, you don't want to overspray too much. I imagine your MK3 will have a similar configuration.

[SuperSpartan]

I have the same issue, could you possibly post those pictures up please? My bay is really confusing with all the stuff in it and i hardly can tell whats what. Im also wondering where can i just purchase a new or refurbished cold start injector?