Dragons91RS

for the past couple of days after driving a bit my ses light will come on and then when I stop for a stop light or some thing else of that nature my car will run like crap. hesitation, acceleration is very slow like it is hard for the engine and it wont shift till after 5000rpm. If I pull over and turn the car off for a few seconds then restart, it will run fine.
I checked the codes, and other than 32 for the egr system(which the car has set since I got it in Jan) Im only getting code 43 ESC.
by the description in my Haynes manual "Loss of the ESC signal to the ecm will cause the ecm to constantly retard EST. This will resualt in sluggish performance."
to me that sounds like my problem. now what I dont know is how to fix it. do I need to replace my ESC sensor(knock sensor) and ESC module. or is there some thing else I should try?
Also if replacement of the above two esc components are what I need to fix the problem can I get buy with turning the car off and restarting it when this happens till next pay day(2weeks)?

RBob

iTrader: (1)

Like I tell everyone: you can throw parts at a problem and hope, or you can check (diagnose) the problem.

Code 43 is set by one of two different ECM tests. The first test is run-away knock. If within a period of 3.9 seconds more then ~245 knock counts are detected code 43 will be set. This can be caused by an open wire or a non-existent knock filter.

The other test is that the ECM will advance the spark timing in order to force knock (detonation). The ECM will attempt this twice, the second time with more advance then the first. If both forced knock tests fail code 43 will be set.

The forced knock test takes place under PE conditions. Once knock is detected PE and HighWay SA is now in effect and the forced knock test is done.

RBob.

Edit: Don't be too quick to discount the EGR code. Excess EGR during the forced knock test can/may supress the knock. This will lead to a code 43.

Dragons91RS

ok can you give me an idea of where I should start looking to diagnose this problem?
honestly I have no idea how or what to check, and for this problem my Haynes manual basicaly says to just change the ESC sensor and module

ok putting that with what my Haynes manual says would completly eleminate the egr as part of the problem.
you say excess EGR can suppress knock, and according to my manual supressed or no knock present will set code 43 and the ECM will controll EST as if there is no knock which will cause severe knock.
Im having completly oppisite symptoms. I have little/no knock but Im getting code 43 and the ECM is retarding the EST as if I have severe knock.

If Im completly off here please tell me. Ive gota learn some how, Im just trying to put together what you said and what the Haynes manual says and make a little sence from it to try and narrow down what the prob could be.

RBob

iTrader: (1)

Hook up a scan tool and check the knock counts. If the counts are constantly incrementing then you have run-away knock. You then have either an open wire or the filter is bad.

If after some spirited driving there is no knock and code 43 pops up, then either knock did not occur or the knock sensor/filter is not reporting it. If no knock is reported then test the system by holding the rpms > 1200-1400 RPM and rap on the engine block. This should be picked up as knock.

If so then you'll need to figure out why the ECM can't force the knock. Check the timing and the EGR system. Have you checked to see if the chip is stock? Maybe running 93 octane can do it?

If the EGR is active during the forced knock test, the test may fail. When the test fails and code 43 is reported the ECM pulls 8-10 deg of SA out all of the time.

RBob.

Dragons91RS

ok off the top of my head I always run Exxon 93+ octane. its the only gas I use, but Ive been using it since I got the car with no prob's till now.
I did adjust the timing down a bit last week by the dis, maybe I should try putting it back where it was?
The other stuff you said I'll give a try. Im gona have to try and find some one with a scan tool, cause right now I cant afford to take it to the dealer or some other place like that

sparks383iroc

RBob,

By open wire, do you mean a wire from the ESC module or knock sensor being inadverdantly grounded out? I've just encountered run away knock last night in test run, with an inordinate amount of spark counts (several hundred). My scan tool (EASE) also was showing for 3 time frames a total spark advance of 23000 deg (not a typo) and then it threw the code 43.

Sparks a flyin'

RBob

iTrader: (1)

Open wire between knock module (filter) and the ECM.

The knock sensor wire being grounded would cause a failure of the forced knock test. Unless the ground was intermittent then it could cause the run-away knock failure.

RBob.

badxs

how often would you say the ecm is actually the cause of this problem?where is the knock filter? should i just check for continuity, or what voltages am i looking for b+, b-, 5. v(from esc module and ecm)???