Ok guys I have seen alot of threads but not quite what I am looking for.

I have an 89 Iroc with the 5.7 and it's always been hard to start cold (still is) is cranks for a few secs then fires sometimes I have to try twice.

When it is running it runs fine.

This year however the cold starting is the same, but now when the engine is hot/warm is won't start correctly and I have to wait a minute or so and I have to crank 3,4 times. Also I find it starts better hot if I just crank it shortly if I crank for any length of time it doesn't want to start.

I cleaned the key and sprayed WD40 in the ignition thinking the VATS what not allowing fuel????

I took the cap off today and there was some buildup on the rotor and the cap terminals (inside cap) so I cleaned them with a dremel and a sanding disc. (I will be changing the cap and rotor when I can get to a parts store)

Alot of threads mention the CTS switch or sensor? Where is it? Pictures? If the temp gauge works in the car does it get the signal from the CTS or are these totally different CTS=airtemp


I don't think it is flooding I can't really smell gas but after a few tries of not starting you can smell the fuel? (I know I know it sounds like I just described flooding!)

So to test the injectors I unplug the clip and test for 12 OHMs (on the injectors)anything less means?? Leaking??

There are NO autozone's around for miles and I don't think Canadian Tire can test an ignition modules?

BUT I NEED YOUR THOUGHTS ON THIS HOT STARTING PROBLEM!! I am thinking the CTS (where ever that is) is telling the ECM that the engine is too cold and is still adding the same fuel.

HOW do you test a CTS???

Oh BTW here are my new C6's

 

Just to add to my previous post.

I just went out and checked the resistance on all the injectors, the lowest one I got was around 16.7.

Does anybody know how to test the CTS? I am assuming that is the one under the coolant hose at the front of the intake?

 

i need to know how to test my cts as well.

a search brought me to this thread, but still no answers

 

mine does the same thing, and its because it runs very rich and floods itself. so maybe your o2 sensors are out? thats whats happening with mine and i just havent gotten around to fixing it.

 

Coolant temperature sensor. CTS . It's located in the front of the intake I think( is on TBI ) . They are like 20 bucks to go get , just get a new one. You have any codes ?

The CTS , it controlls a?F ratio based on engine temps . If it's outta wack, the computer thinks it's either one eztreme or another for temps. So , it adjusts the fuel accordingly.


Reading the codes , it should have stored one if the sensor is gone. Do you have a haynes manual , if not you should get one , they are so worth it for stuff like looking for sensors.

 

Also check the CTS connector for corrosion, I speak from experience

 

No corrosion at the CTS connection and still I couldn't find out how to test the CTS I just went out and bought a new one and replaced it, at the same time I did a new cap and rotor.

the problem is still there! I checked for codes before I removed and replaced the CTS (there were no codes) it just kept flashing code 12 over and over and over. I know that it should flash code 12 three times before displaying any new stored codes but there is nothing!

Here was my theory: The CTS was shot so the computer was thinking the engine was stone cold and kept enriching the fuel when it was hot (flooding it or just too much fuel)

Ok so now I think I was wrong, I thought the CTS was in charge of putting the computer into close loop operation (engine at operating temp) I am assuming that there is other sensors and or factors that put the engine into closed loop

The oxygen sensor is starting to sound like a good point to check as it seems to be missing now when it is running and warm?

Ok I don't have a fuel pressure gauge either so I am not sure I have good fuel pressure when it is running. Anybody know what pressure I should see when it is running? It's a stock 89 350TPI with no mods, and how much should a fuel pressure gauge run me?

 

On startup? Could be a bad FPR or a couple leaky injectors.

 

To clarify a bit, the main problem is the hot restarting problem. I can live with the cold starting delay (cranks for a few seconds before it starts) I know there is some "Chip Tweaking" that can probably fix the first start/cold start by introducing fuel to the injectors earlier?? (I can't wait to begin chip tuning sorta like I can't wait to have my teeth pulled )

Anyway can someone recommend a good fuel pressure gauge (brand) that I could get in Canada if possible? What other tools would I need/should have? I just hope that it's not the ignition module or dizzy,coil,etc!!!

 

you are in bc canada? which part?

 

I am located in Kitimat population of about 10 000 people! There isn't even a place where I can get a wheel alignment!! Hey Zion aren't you a member of Vancouver F-bodies??

 

maybe...

 

Hey Zion did you ever figure out what was wrong with your motor was it the dizzy?

 

are you on the board as well?

Dizzy + ECM + bad wiring.

 

yah I am, did you troubleshoot it yourself?

 

me and another member. We kinda stumbled across the solution after a series of unfortunate events...


what is your name on the board?

 

I don't have the table near by, but when cold, resistance on the CTS is high, up in the 200K ohm range, to when it's warm, all the way to near zero ohms.

Pretty sure that Chilton and Haynes manuals have the "Ohms vs Temp" tables in them.

But, I'd start with checking fuel pressure at start up. Then possibly IAC may have a problem...IAC is what allows more/less air in at start up and idle (based off CTS though).

Might be as simple as taking the TB apart and cleaning it up and it's passages.

Ckecked the TPS voltage yet?