Guru's- Need help with coldstart issue
#1
^Hold On
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Guru's- Need help with coldstart issue
Awhile back I had a tech who works at the dealership take off my top manifold and replace the small coolant hose cause it was leaking. Come to find out he is an idiot who thinks he knows rotaries. He capped off my BOV and messed with the idle screw thats never suppose to be touched. This is when I decided to learn how to work on my car. After he touched my car it wouldn't idle the next morning.
Symptoms- Car will start for about 2 seconds then sputter and die. If I keep my foot on it the car will run. After about 17 seconds of giving it gas the car will idle fine and drive great. This idiot must have damaged something or put it back wrong. I've included some pics of my thermowax casue I think this is the problem. I have no vac leaks cause the car idles fine when warm. Should I replace the thermowax? Maybe clean it? Anything I should check?Help ME- Matt
Symptoms- Car will start for about 2 seconds then sputter and die. If I keep my foot on it the car will run. After about 17 seconds of giving it gas the car will idle fine and drive great. This idiot must have damaged something or put it back wrong. I've included some pics of my thermowax casue I think this is the problem. I have no vac leaks cause the car idles fine when warm. Should I replace the thermowax? Maybe clean it? Anything I should check?Help ME- Matt
#2
HAILERS
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It's a classic sign of the water thermo sensor on the back of the water pump HOUSING being disconnected. If it is disconnected, the ECU defaults to a temp of 180*F. Meaning, the ECU duing START, will inject too little fuel.
Later when the engine is fully warmed up, the car should start easily/normally, because.............the defalut of 180* is just about what a fully hot engine runs at.
The sensor has two wires, and has a green plug, or is it the jack that's green. Just take a look with a flashlight.
Then again, if that was so, you would have a fault for that sensor when you went to look for fault codes.
Later when the engine is fully warmed up, the car should start easily/normally, because.............the defalut of 180* is just about what a fully hot engine runs at.
The sensor has two wires, and has a green plug, or is it the jack that's green. Just take a look with a flashlight.
Then again, if that was so, you would have a fault for that sensor when you went to look for fault codes.
#4
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i don't think it would be the coolant temp sensor because he said it runs fine after only a few seconds of holding the throttle open from a cold start. how would the engine be warm after only 17 seconds of holding the throttle.
i had the same symptoms, i had to hold the throttle open only on cold starts. i would suggest blowing compressed air through the coolant passages and coolant hoses in the throttle body to make sure they are clear. after they are definitely clear hook up the coolant lines put everything back in place and make sure the thermowax is adjusted properly, check the FSM to see where it needs to be adjusted. then bleed the coolant system thoroughly to make sure the thermowax is operating as it should, mine took a while to get coolant to reach the thermowax.
your thermowax looks to be within proper spec but it is hard to see clearly in the pics. try turning the screw to the left when you attempt to start and see if it holds the cold idle. don't turn too much, just a few turns...try a start. if it still won't start on it's own turn a little more. you should also use a mirror so you can see what you are doing while you are making adjustments.
after looking closer it seems that the thermowax is OUT of adjustment. turn the screw left until the cam is on the other mark! if you don't know what i mean pm me.
i had the same symptoms, i had to hold the throttle open only on cold starts. i would suggest blowing compressed air through the coolant passages and coolant hoses in the throttle body to make sure they are clear. after they are definitely clear hook up the coolant lines put everything back in place and make sure the thermowax is adjusted properly, check the FSM to see where it needs to be adjusted. then bleed the coolant system thoroughly to make sure the thermowax is operating as it should, mine took a while to get coolant to reach the thermowax.
your thermowax looks to be within proper spec but it is hard to see clearly in the pics. try turning the screw to the left when you attempt to start and see if it holds the cold idle. don't turn too much, just a few turns...try a start. if it still won't start on it's own turn a little more. you should also use a mirror so you can see what you are doing while you are making adjustments.
after looking closer it seems that the thermowax is OUT of adjustment. turn the screw left until the cam is on the other mark! if you don't know what i mean pm me.
#6
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And somehow, some way, after seventeen seconds of throttle, the thermowax piston retreated into itself , and thereby cracked the throttle plates open. Uh huh. Sho'nuf.
About as impressive as my 17 second warm up. humor
About as impressive as my 17 second warm up. humor
#7
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Looks like my thermowax is off. The throttlebody is off the car meaning it is cold. The thermowax (cam roller) is set to #2 right now. Just want to confirm that it is off. Looking at the factory service manual thats what is says.
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#8
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It's the mark most distant from the thermowax piston. In other words I think you have the wrong mark ...marked.
Get a tea pot of boiling water. Pour it over the outer surface of the thermowax. Watch the piston expand. The cam will move off the roll pin. The last mark to move over the rollpin is the right mark. Remember the temperature in the FSM. Seventy something degrees.
The more you turn the screw that sits on top of the thermowax piston, in a clockwise direction, the sooner the throttle plates will close i.e. the sooner the cam come off the rollpin.
Get a tea pot of boiling water. Pour it over the outer surface of the thermowax. Watch the piston expand. The cam will move off the roll pin. The last mark to move over the rollpin is the right mark. Remember the temperature in the FSM. Seventy something degrees.
The more you turn the screw that sits on top of the thermowax piston, in a clockwise direction, the sooner the throttle plates will close i.e. the sooner the cam come off the rollpin.
Last edited by HAILERS; 11-19-08 at 05:14 PM.
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