QuestionQUESTION: We have a 98 Breeze 2.4 in the shop that will when the cruise control is turned on. It will not restart for a while after this occurs. Any suggestions on what direction to go with this?
ANSWER: Hi Lee,
"that will... when the cruise control is turned on"? I assume that you mean "die". Have they tried to do a fault code readout with the plug-in code reader? What codes did they get? Other than that which might explain an electrical short that takes out ignition system, I would suspect that one of the vacuum hoses from the power brake system to the reservoir of the reservoir to the servo, of the servo itself leaks when activated (which is probably the most likely of the three places such that the mixture gets leaned out due to the leak of air going back and into the intake manifold. So that can be checked with a vacuum gauge to see whehter the serov holds a vacuum or not. So those are the two possible ways to go forward from here.
Roland
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QUESTION: Roland,
The vehicle is in the service bay at idle. When the cruise control button is applied, the vehicle stalls then will not restart right away. We lose fuel pressure as well. There are no DTC's current. In history the was one for a cam/crank sensor error, but those seem to be functioning properly at this time. We have tried to see if the servo is in the equation by disconnecting vacuum and electric to it, the problem did not change.
AnswerHi Lee,
I don't see anything in the function of the cruise control that would shut down the engine. Even a short in the wires of the system would not appear to be able to stall the engine electrically. The control has a single wire that goes to 41 of the pcm arriving on a red/lighht green wire at that pin. There is a blue 20-pin disconnect under the dash at the junction block (rear side of the fuse block) and pin 3 of that disconnect has the red/light green on one side and a pink/light green on the other side that goes to the clockspring on the steering column and to the cruise control. All the control does is modify the resistance to ground shown to that wire when the various switches of the control are operated. So there would seem to me to be either a short/open in an internal resistor in the control such that when activated the pcm says to itself "I don't like the resistance I see, so I am going to turn off the engine". There should be 5 different resistance to ground (one at rest, and 4 others when each of the four switches on the control is activated). The rest position should show the highest resistance to ground on that wire, and each of the other 4 would be a lesser but different resistance. Maybe that wire is shorted to a voltage source or who knows, but check the resistance to ground shown by the pink light/green with the 20-pin disconnected would be my suggestion.
When you say 'disconnected the vacuum', do you mean that you disconnected the hose at the power brake and plugged it? If not, then maybe you still are dealing with a vacuum leak causing the stall. If so, then that would appear to take that possibility off the table. Very interesting...
Roland
PS You don't happen to have the 'autostick' option?
PPS One possibility is that there is a short between the cruise control wire and an adjacent wire on pin 4 of the 20-pin disconnect which carries digital data information which if shorted might take down the ignition system. That wire connects to pin 6 of the data link connecter socket, the plug that is under the dash where the fault code reader can be plugged. Try measuring the resistance to ground of that pin 6 with the engine 'off', then push the speed control switch that is causing the stall out and note whether the resistance on that pin 6 shows any sign of change in resistance. If so, that would explain the cause.
I will look forward to learning what resolves the problem.
