QuestionHi Roland,
I had been previously corresponding to you about subject vehicle, but when I tried to do another follow-up question, it said I had too many follow-ups, so here is a new chain. The following was your last response:
Subject: '95 Concorde: no start
Answer: Hi Ken,
Do you have spark when you are cranking it over? I assume that the fuel pump still runs for about a second when you first turn the key to run. Ideally it should run while you are cranking it also, but it will be difficult to hear it. You could remove the fuel pump access cover under the floor mat in the trunk and have a helper verify that it runs while you are cranking it. If you don't have spark/fuel pump while cranking it then try removing the ASD relay and jumping from the rear pin of the socket to the front pin which will fire up the coil pack and the fuel pump. Then try and start it. If it starts, then either the asd relay is no good, or the signal from one or the other engine position sensors is weak enough to cause the pcm to kill the ASD relay, but without setting the codes. If it doesn't start and you don't have spark, then that does suggest one of the sensors or its wiring is bad, but why no codes is a puzzle.
If you have spark and fuel pump and still no start, then I would check the egr valve to make sure that it isn't stuck ajar. Spray some WD-40 on the stem where it enters the body of the valve and move the stem back and forth with the tip of a screwdriver inserted in the slot of the valve stem. It should close to a dead stop by means of the internal spring-action. If that valve were ajar the mixture would be too lean to sustain an idle. The valve is under the throttle body mounted in a pipe that runs from the exhaust manifold on firewall side of the engine back to where the throttle body is located.
Roland
I was able to get back to the car today to take a look at your suggestions on what to try to see if that would work. Here is what I did and what I discovered:
I checked the fuel pump and it was good, both with key in initial on position and while cranking the engine over. I also have spark at the end of the wire. I also checked spark with a plug in the wire to ensure there was enough juice to push thru the plug and there was a nice strong spark. I took a look at the EGR valve the best I could, but was difficult to see if the valve was open or not. I attempted to move with a screwdrive and the spring was nice and free and did not appear to be sticking, but I was unable to tell if the actual valve was open or closed. I believe it was closed as best I could tell.
I took another look at the injectors, thinking perhaps they were not getting power to function. Resistance was good and voltage was good while cranking engine, so that does not seem to be the issue either.
I took a look at both the camshaft and crankshaft position sensors. Both sensors had good voltage while unplugged and key in on position. While plugged and backprobed with meter, both had good voltage while cranking engine and seemed to be sensing the cam/crankshaft as it passed the sensor.
Going back to basics, I thought perhaps the mechanical timing might somehow be off enough to keep it from running, although really didn't think this was it either. I pulled the plug again and hooked it back to the plug wire. While placing my hand over the plug hole to feel the compression as the cylinder reached TDC, I watched the plug spark, which seemed to be good; however, this was when I noticed something odd, at least to me anyway as I had never seen it before. The plug sparked twice, once at or near TDC and again during the power stroke. Is this normal?? I checked more than one plug with same result. Also, I noticed there seemed to be a lot of fuel getting into the cylinder as the plugs were very wet and my hand was also very wet (almost dripping) from fuel after feeling the compression. Is it possible the engine could be flooding out keeping it from starting?
There seems to be all the basic requirements for an internal combustion engine to start...air, fuel, compression and spark...but still not starting. I figure if you don't have any recommendations, I will finally admit I can't figure it out and get it to the dealer and pay the price. Thanks again for your time and efforts. I hope you had a great Thanksgiving!!
Best Regards, Ken
AnswerHi Ken,
The race for "expert of the month" is going down to the wire.
Chrysler "repairer" vs Microsoft "coder".
One vote per answer is permitted.
Deadline to vote is Thursday, 4 PM CT.
Click on "Thank/rate" button below, then click on "Yes" for nomination.
Thanks
Hi Ken,
Have you solved the 'no start'? If you would like to tell me there is a "Thank/rate the expert" button below which if you click will take you to a page where you can "comment".
May I also ask a favor? On that same page you will see the question "Would you like to nominate this expert to be 'volunteer of the month"? If you will click on "Yes" that would be appreciated. I am competing for that recognition which is based on nominations from questioners like yourself. Achieving it will increase awareness of the Chrysler repair category.
Roland
Hi Ken,
The double spark is normal as there are only three section of the coil pack to run the 6 plugs, and of course no distributor, so what happens is the spark plug is fired twice as often as necessary because of its 'mate' cylinder needing to be sparked. If the headlight flashing/theft system is still abated, then it sure sounds to me like it aught to start.
The egr stem should come to a dead stop in the direction the spring is trying to move so push it further in the same direction to see if will close any further. You might do well to remove it and clean the interior of the valve body with a stiff wire in case the ability to close is mechanically restricted by crud built up inside the valve.
With still no codes, but having spark, fuel, compression I have to think 'mixture' and the egr is the only thing that isn't well-sensed by the fault detection system. Because of the no start I would not be too surprised to find unburnt fuel in the combustion chamber. But that doesn't mean the mixture is right.
Try doing the egr approach I suggested above and let me know if that works. Other than that check for fault codes again.
Roland
