What am I looking at?

[DanMcG]

In front of the starter off the side of the block there's an electrical something, what is it?

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It's an 1985 k10 350

I'd do a search but I don't know what to look for. Thanks.

 

[Honky Kong jr]

@chengny @hatzie @1987 GMC Jimmy

 

[HotRodPC]

Knock Sensor for ESC.

 

[HotRodPC]

That knock sensor was first found on LE9 305's with Electronic Spark Control. The ESC is a stand alone ECM behind the glove box with a small harness that goes to the Knock Sensor, the distributor, that 4 prong plug that hangs off it and then to the Vacuum Tip In switch. That's all there is to the ESC. Not a bad system on paper. It allows the ICM aka Igntion Control Module to time the engine. That's why the ESC ICMs have more prongs. The purpose of ESC is advance the timing as far as possible without having detonation. As soon as detonation is detected from the knock sensor the timing is retarded just enough to kill the detonation, engine knock or pinging, whichever term you like to use. ESC was also incorporated with the CCC (Computer Command Control) system where the Electronic carb was used with a throttle position sensor and A/F ratio adjusting solenoid. That way igntion timing and air fuel ratio was alway being motitored and adjusted by the ECM.

 

[hatzie]

That knock sensor was first found on LE9 305's with Electronic Spark Control. The ESC is a stand alone ECM behind the glove box with a small harness that goes to the Knock Sensor, the distributor, that 4 prong plug that hangs off it and then to the Vacuum Tip In switch. That's all there is to the ESC. Not a bad system on paper. It allows the ICM aka Igntion Control Module to time the engine. That's why the ESC ICMs have more prongs. The purpose of ESC is advance the timing as far as possible without having detonation. As soon as detonation is detected from the knock sensor the timing is retarded just enough to kill the detonation, engine knock or pinging, whichever term you like to use. ESC was also incorporated with the CCC (Computer Command Control) system where the Electronic carb was used with a throttle position sensor and A/F ratio adjusting solenoid. That way igntion timing and air fuel ratio was alway being motitored and adjusted by the ECM.

Some of the Pre-87 Cali emissions had an O2 and MAP sensor on the CLCC Closed Loop Computer Control ECM for the electronic Rochester... The ESC was built into the Cali CLCC ECM. You'll find the Metripack 280 ALDL jack on these rigs.

 

[HotRodPC]

Some of the Pre-87 Cali emissions had an O2 and MAP sensor on the CLCC Closed Loop Computer Control ECM for the electronic Rochester... The ESC was built into the Cali CLCC ECM. You'll find the Metripack 280 ALDL jack on these rigs.

You're exactly right. All the CCC had O2 and MAP sensors. That's where it got the info to adjust the AF Solenoid by the ECM and the ESC was also incorporated into the CCC. I think what you're referring to as CLCC is CCC. I've never heard it called that before. I knew of the C4 which is Computer Controlled Catalytic Computer and was the first Closed Loop Feedback computer system, then the CCC that was Computer Command Control. Maybe both C4 and CCC are considered CLCC but to the best of my knowledge those were the first GM computer system. Technically, the ESC was aslo a computer system but it was only for Spark timing as a stand alone and didn't do anything with the Carb or A/F ratio.

 

[hatzie]

You're exactly right. All the CCC had O2 and MAP sensors. That's where it got the info to adjust the AF Solenoid by the ECM and the ESC was also incorporated into the CCC. I think what you're referring to as CLCC is CCC. I've never heard it called that before. I knew of the C4 which is Computer Controlled Catalytic Computer and was the first Closed Loop Feedback computer system, then the CCC that was Computer Command Control. Maybe both C4 and CCC are considered CLCC but to the best of my knowledge, those were the first GM computer system. Technically, the ESC was also a computer system but it was only for Spark timing as a stand-alone and didn't do anything with the Carb or A/F ratio.

If you look in the 85 & 86 light truck wiring diagrams and service manuals you'll find reference to CLCC. I used the definition GM gave that acronym in the service docs. I've heard it called Closed Loop Carburetor Control too along with C3 & C4. These were the very earliest embryonic GM computer controlled fuel systems. Not very bright. Many of these early ECMs didn't even have a microprocessor they were just simple state machines. I believe the Cadillac division used them in 1979 or so.

 

[Rusty Nail]

FIGHT! FIGHT!

 

[HotRodPC]

Ain't no fight. I'm just saying I've never heard it called what he has.

GM Started computer with the C4 starting as early 78 IIRC. G body for example, Buick Regals and Olds Cutlass may have got it, but Pontaic Grand Prix, Bonneville did not, either did Chevy Malibu, Monte Carlo but El Camino might have. I'm not positive of the break down now. Been a long long time without looking it up. Cali trucks had CCC before 49 States truck did.

 

[HotRodPC]

Here is info from GM Heritage. So it does appear as I suggested, the CLCC term hatzie is using is would cover C4 and CCC systems. CLCC seems to be the type of system it is when referred to, not the actual name of the system. Both C4 and CCC were CLCC systems. Notice it even includes C4 and TBI in the CLCC type when TBI is inejection, not a carb. It still monitoring the same parameters though and also making the same adjustments in real time as you're driving. Being this statement was recorded in Feb 79, CCC had not been implemented yet and may be why it's not mentioned in this article below.

The Emission Control Project Center was established on August 3, 1977, by Mr. E.M. Estes to "have the overall responsibility for the design and development of the carbureted and fuel injected closed loop 3-way catalyst system including related electronic controls, fuel metering, spark control, idle speed control, EGR, etc. currently planned through 1981." (This statement was recorded February 2nd, 1979)



The system implementation will be phased in over three years. In the 1979 model year, California vehicles with 2.5, 2.8 and 3.8 liter engines will have a CLCC system. In 1980 model year, vehicles sold in California and 3.8 and 4.3 liter engines sold Federally will have CLCC and, finally in the 1981 model year all passenger cars. California light and Medium duty trucks may also use the c-4 system. While 1979 and 1980 systems are very similar, the 1981 system (2nd generation) will differ in that it may include additional engine control systems (i.e., electronic spark timing, idle speed control, etc.).

The Emission Control System under development has been designated C-4. This stands for Computer Controlled Catalytic Converter. The C-4 System encompasses Closed Loop Carburetor Control (CLCC) and Throttle Body Injection (TBI) systems."

 

[Rusty Nail]

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[chengny]

enzyme. [(en-zeyem)] A protein that causes other organic molecules to enter into chemical reactions with one another but is itself unaffected by these reactions.

 

[HotRodPC]

Ain't no fight'in, Ain't no reason to rumble so it Ain't gonna happen.

In fact, I don't even think it was an argument. Why would it be? It appears we're both right. CLCC is a TYPE of computer system, C4 and CCC are names of the computer systems. So what's the issue? Ain't one. Though I did learn about CLCC, cuz I'd never had heard the term before.

Now that Rusty made me say Ain't 4 times, now we have an issue.