Major hesitation and low rmp issues hey guys, My 93 2.3 mustang is still troubling me. It has a really bad hesitation sometimes off the line, and when it is either put into gear after start-up, or after being reved high, the rpm's drop so much that it feels like it's going to stall. The vaccume pressure is low, but constant at 15psi. I had the car code checked and it came up with fuel pressure regulator, maf, o2 sensor, and coolent thermostate. i have a performance headder on it and a cold air intake. The tranny is the a4ld. Any ideas guys?
I wish I knew man mine does the same thing. I also have a '93 with the a4LD and have just learned to feather the throttle on take off before laying into it. If I give mine alot of gas on take off it bogs down and feels as though it might die. Then it will just all of a sudden clear up and take off.
yeah, what ever it is, we have the exact same problem. Could you do me a favor and see what your vaccuum pressure is? Mine's steady at 15 and I'm woundering if that is the problem, or if its something different. I changed the spark plugs, wires, fuel filter, checked my fuel pressure regulator and it's ok. The only thing i can think of is the maf or the O2 sensor, and possibly the low vaccum. I wounder what your vaccume pressure is and if you have done anything to your exaust. I have a feeling it is the maf, but thats an expensive project and i want to be sure. Thanks man
is it holding steady vacuum or is it floating around? leave the vacuum gauge on it and go drive it hard and see what happends. if it holds consistant vacuum at 15 its ok dont really worry about it. probably the tps is out of wack
when i was checking it i played with the throttle at different rpms and punching it to see what it does, but it stayes constant at 15. If thats not the problem, what could it be?
Couple of suggestions... We need a bit more idea of vacuum. It is typically measured in inches of mercury, ie, 15 in Hg, or below atmospheric, unless you have a turbo and this the boost level.... To me, 15 in sounds low for a normal stock engine, it should be 19-21 in at idle. Check for vacuum leaks. If no leaks, check the base timing setting. Low vacuum will affect the performance of the fuel pressure regulator. Since you have the codes, you should troubleshoot the items the codes indicated. Also, it may be worth checking the tps, since that is what initiates the idle sequence.
You might want to try checking your fuel pressure. Your regulator might be bad. Or it could also be the ignition; I had my ignition control module go bad. My car would lose power and then kick right back to normal, replace it problem solved.
the pressure regulator should be ok, i pulled the vaccume line on it and it was dry. How would i check the ignition module w/o having to replace it?
you said you got a code for coolent thermostat? Do you mean the coolent temp. sensor? I dont think that your computer could throw codes about the thermostat. But there is a sensor that tells the computer the tempature of the coolent, so that it can adjust your timing, mainly for easier starting in winter. If that sensor has gone bad, it could be what your looking for.
