HI ALL,

I have a 91 Formula TPI 305 and my SES flashed a code so I checked it reads 43 so I take it I have a CODE 43. In my book it says EST ECM related error so I am wondering if I have to start throwing parts at this thing yet ? The manual is very unclear about what to do next ?

The car runs fine until it warms up or is in closed loop then it occasionally loses ALL power under acceleration misfiring badly. The power comes back usually, but in jerking motions. If you let it sit for a few minutes it calms down and behaves ok until the next incident. My car has about 50,000 miles on it and is pretty much stock.

Any suggestions ? Would really appreciate some help my car is dead !

BB

 

This may help if you can't find the cause.

Had same problem last year on my low mileage 91 TPI - but don't remember code #.

Have your injectors checked - You don't need to take them out but do a cold and hot ohm reading. If they drop by much when their hot they're no good. I think 15 is a good reading.

When injectors are shorting they can still work okay until they warm up.

 

I having the same problem. Did you ever get the problem resolved? Was it the injectors?

 

Had the same prob. Do you loose ALL electrical power? No Radio, lights power windows? All that happened to me, code 43 etc. Turned out that I had a bad connection inside the starter causing disconnect of electrical power. I'd start with checking all your connections to the starter...........then check all electrical power source connections, like battery etc.....

 

Check your connections at the distributor. The last time I got an EST related error, I accidentally had the timing-bypass connector wire pinched under the distributor hold-down clamp- essentially grounding it out.

 

So far I have replaced the Ignition module also known as the ESC. It sits in the distributor.

The SES light used to come on after the car warmed up now it comes on within 2-3 minutes of starting the car. I've cleared the codes and a 43 shows up right away. GM calls it ESC/knock sensor related. Low voltage on the line maybe even the ECM.

The car runs strong then loses power then stumbles then the power is back. I am replacing the knock sensor this weekend. See if that fixes it ?

BB

 

Get your knock sensor from the dealer (well check with them first) because they had a recall on many of these.

Bugsy

 

First of all Welcome!!

Now as for these above statements..Your car is a 91 TPI as you said, correct?? Yes.. So. the Ignition Module, and the ESC are two different things..The piece you are referring to inside the distributor, Is in fact the Ignition Module, but NOT the ESC module... On 90 - 92 model TPI's or, Speed Density system..the ESC module is built into the Prom or Memcal inside the ECM.. Your best bet it to check the Knock Senor first, can be a common problem, and most likely to be cheaper to replace then the Memcal and ECM... If the knock sensor doesn't solve the problem, double check all the wires, to and from this particular system... If all is good, and the code is still there..you may either need a new Memcal, or even worse a ECM... Hope this helps you some....

 

Update, changed out the k/s and the code 43 went away. Easy fix after all.

BB

 

Glad it was that easy for you..Let her rip!!