Code 42--EST monitor line failure

[V6POWER]

The car just set a code 42. Where is the EST monitor line and how do I fix it? Is the EST the same as the ESC? Would this affect my IAC counts and BLM numbers? I had good IAC/BLM (16/128) at idle in park until this code set. Now the numbers are inconsistent. Thanks.

 

[Jimn8or]

Don't see it in your sig, but the only time my car threw a 42 was before I grounded my Direct Scan cable. You can try resetting the ecm and see if the code comes back as a start. Failing either of these, PM SalvageV6 as he is the resident electrical Guru and knows these cars extrememly well.
HTH
Jim

 

[salvageV6]

Just posted at the other site. Same question.

Not the same circuit as the ESC module.

 

[V6POWER]

Jim--I reset the ECM and the code returned.

salvageV6--I was going to buy a new ESC module and try that but are you saying above that it is not the ESC (EST) module causing the problem? Thanks.

 

[V6POWER]

Any more help please. I would like to resolve this problem before Bristol. TIA.

 

[V6POWER]

I took off the connectors and sprayed them with tuner cleaner. So far the code 42 has not reappeared.

 

[ijames]

My car would set a code 42 every now and then, along with other occasional codes and hiccups. After 9 months of checking and replacing stuff, connecting and disconnecting DirectScan, and after myself and at least 3 other people had had their hands on the grounds at the back of the passenger head (including one trans rebuild where the trans guy also checked the wires for me and his day job is as a professional electrician), where nothing anyone did could cause the error, one of the ground wires finally broke off and was hanging in midair. My guess is that the wires broke inside the insulation which still gave a connection most of the time but it took a long time for the insulation to let go so we could find it.

The ESC module is the flat square block on the passenger inner fender. It processes the knock sensor signal and sends it on the ecm. I think the EST line goes to the ignition module and is either what the ecm uses to control the timing or is the signal line to tell the module that the ecm is controlling the timing. Check the wiring diagrams online at www.gnttype.org . I don't think I've ever heard of an ESC module going bad but I'm sure someone's has.

 

[V6POWER]

Thanks for the additional info ijames. It may come in handy if the code returns.

 

[salvageV6]

Posted again on the S site.

Don't buy the ESC module for an EST problem.

It's the module under the coil pack or it's wiring to the ECM or the connectors themelves.

Spraying the ECM is a good idea, as would spraying the module connector under the coil pack. Remove the bolt first.

 

[V6POWER]

salvageV6--I also removed/sprayed the module connector under the coil pack. So far, so good.

I sure did get a lot of good info from eveyone so in case this ever happens again I will know what else to check. Thanks again to all.

 

[Swt_86]

You mentioned "tuner cleaner" for spraying the connections. Is this the ticket for corroded contacts (like my chime module that sounds posessed from time to time) I'm assuming they sell it at like a Radio Shack? Thanks.

 

[V6POWER]

My 'tuner cleaner' came from Radio Shack. The can says it 'cleans' but it will probably depend on how corroded the terminals are. A can can't be that expensive so give it a try.

 

[Swt_86]

Thanks. I'm off to Radio Shack to get a can and give it a try!