MonteCarloSS.com
MonteCarloSS.com

CELEBRATING 20 YEARS!

Previous Thread
Next Thread
Print Thread
#1067224 - 07/10/20 11:26 PM Code 43  
Joined: May 2007
Posts: 89
1988SS Offline
10+ Year
1988SS  Offline
10+ Year
Member

Joined: May 2007
Posts: 89
Georgetown, TX
1988 SS with 350...all the CCC etc still intact so basically stock other than the 350.

Every once a while....under hard acceleration. I will get a Code 43 (The ESC retard signal has been on for too long or the system has failed a functional test).

Actually it hasn't thrown the code in quite awhile, but today I had the AC on and I put the pedal down...and the check engine light came on (hate that dang thing). Car goes into a limp home mode until you shut it down and start it again.

Any suggestions or thoughts (besides removing the computer).

Thanks,
Darron


1988 Monte Carlo SS
#1067225 - 07/11/20 12:05 AM Re: Code 43 [Re: 1988SS]  
Joined: May 2000
Posts: 1,716
BadSS Offline
20+ Year
BadSS  Offline
20+ Year
Member

Joined: May 2000
Posts: 1,716
Pearl, MS, 39208
They call it that, but it's most common reason for setting that code is knock sensor related

Most likely it is one or more or the two:

1) Open or shorted knock sensor
2) Bad, loose, or not connected knock sensor wire
3) Loose knock sensor
4) Excessive mechanical noise within engine
5) Improperly set base timing

I'd check the wire to the sensor first, if OK I'd check the base timing, if OK I'd check for possible rattles in the exhaust system. If all checked out OK, I'd replace the knock sensor.

#1067227 - 07/11/20 03:10 PM Re: Code 43 [Re: 1988SS]  
Joined: May 2007
Posts: 4,852
Buick Runner Online content
10+ Year
Buick Runner  Online Content
10+ Year
Member

Joined: May 2007
Posts: 4,852
Dharma station 1 the Hydra
Also make sure the ESC module is getting full 12 volts.


SBC powered 1987 Regal with TES headers, ZZ4 intake, ZZ4 PROM chip, mini starter, THM2004R, 2500 stall converter, 2040 cam, CCC system, and 3.73 posi rear.

2008 ex NPS P71 Crown Victoria, cop motor, cop shocks, cop brakes, and Jmod.

Never argue with an idiot.
They will just drag you down to their level and beat you with experience.
#1067228 - 07/11/20 03:29 PM Re: Code 43 [Re: 1988SS]  
Joined: May 2007
Posts: 89
1988SS Offline
10+ Year
1988SS  Offline
10+ Year
Member

Joined: May 2007
Posts: 89
Georgetown, TX
Thanks for the suggestions!


1988 Monte Carlo SS
#1067231 - 07/11/20 03:46 PM Re: Code 43 [Re: 1988SS]  
Joined: May 2007
Posts: 89
1988SS Offline
10+ Year
1988SS  Offline
10+ Year
Member

Joined: May 2007
Posts: 89
Georgetown, TX
Anyone know what the appropriate GM part number would be for the 350 knock sensor?


1988 Monte Carlo SS
#1067232 - 07/11/20 04:03 PM Re: Code 43 [Re: 1988SS]  
Joined: May 2004
Posts: 961
BladeOfAnduril27 Offline
15+ Year
BladeOfAnduril27  Offline
15+ Year
Member

Joined: May 2004
Posts: 961
Doylestown, PA
Looks like the MCSS used AC Delco 10456287. However, Camaro with a 350 used 10456288. I have no idea what the difference between the two is though, and don't know that it matters.


~ Matt H.

1988 Monte Carlo SS w/ T-tops, White with gray int, 350, Summit cam, World Torquer S/R heads, Holley St. Dominator intake, Edelbrock 600cfm carb, Champion 3-row alum radiator, ramchargers, 200-r4 with CK Shift Kit, billet servo, 2200 stall, Afterburner headers, Pypes 2.5" with x-pipe, Violator mufflers (stock exit), S10 front brake swap.
#1067234 - 07/11/20 04:22 PM Re: Code 43 [Re: BladeOfAnduril27]  
Joined: May 2007
Posts: 89
1988SS Offline
10+ Year
1988SS  Offline
10+ Year
Member

Joined: May 2007
Posts: 89
Georgetown, TX
Originally Posted by BladeOfAnduril27
Looks like the MCSS used AC Delco 10456287. However, Camaro with a 350 used 10456288. I have no idea what the difference between the two is though, and don't know that it matters.

Thanks!


1988 Monte Carlo SS
#1067235 - 07/11/20 06:25 PM Re: Code 43 [Re: 1988SS]  
Joined: Jan 2000
Posts: 4,865
mmc427ss Online content
20+ Year
mmc427ss  Online Content
20+ Year
Member

Joined: Jan 2000
Posts: 4,865
Pottstown, Pa
The knock sensor is sized to the bore of the cylinder. Install a 350 sensor first then chase the problem.

Had a 305 in my 85 Chevy full size van, very simple ECM in that van. The spring in the fuel pump broke which caused the pump arm to rattle, knock sensor picked that up and retarded the timing. Took me while to find that problem.
Bob

#1067237 - 07/11/20 08:55 PM Re: Code 43 [Re: 1988SS]  
Joined: May 2000
Posts: 1,716
BadSS Offline
20+ Year
BadSS  Offline
20+ Year
Member

Joined: May 2000
Posts: 1,716
Pearl, MS, 39208
I can't say with certainty but I do know with the TPIs the knock sensor and the ESC for the 305s and the 350s are different. The harmonics of the 305 and the 350 are different. At least with the TPIs they "matched" those two components. That said, I would not use a 350 knock sensor with the 305's ESC. I swapped a number of 305s in Montes for 355s and 406s using the stock computer, ESC, and 305 knock senor. Everything seemed to work just fine with the 350's, but I did have to wrap the knock sensor's threads with as much teflon tape as I could and it still catch, then tightened it only enough to get it from not leaking. All was well.

Long story short, if the sensor is bad, get a replacement one (305) and wrap the threads a few rotations with teflon tape - I know that'll work just fine.

#1067238 - 07/11/20 09:33 PM Re: Code 43 [Re: 1988SS]  
Joined: May 2007
Posts: 89
1988SS Offline
10+ Year
1988SS  Offline
10+ Year
Member

Joined: May 2007
Posts: 89
Georgetown, TX
I have changed the 305 ESC to the 350 ESC module.

I'm pretty sure the knock sensor is probably 350 but can't be 100% sure since I didn't install myself.

No problems with the knock sensor leaking....so I may have the 350 sensor already in there?


1988 Monte Carlo SS
#1067239 - 07/11/20 10:15 PM Re: Code 43 [Re: 1988SS]  
Joined: May 2000
Posts: 1,716
BadSS Offline
20+ Year
BadSS  Offline
20+ Year
Member

Joined: May 2000
Posts: 1,716
Pearl, MS, 39208
Good deal, since you have the 350 ESC, then you'll need to get the 350 sensor. Could be you still have the 305 sensor and with the 350 ESC,, I could see where that combination would probably be problematic for you.


Original owner of 1985 SS black hardtop w/gray interior. Frame-on restoration - 406 sleeper w/ heavily ported FIRST TPI. However the 1.875" headers, 3.5" duals, TH400, Ford 9", notched frame, and 10-point cage w/swing-out bars might tip you off it's not a lil' ole 305 TPI. Other mods: 2" drop, 18" wheels, f/r disk brakes, and custom stereo system.
#1067242 - 07/12/20 04:00 AM Re: Code 43 [Re: 1988SS]  
Joined: Jan 2000
Posts: 4,865
mmc427ss Online content
20+ Year
mmc427ss  Online Content
20+ Year
Member

Joined: Jan 2000
Posts: 4,865
Pottstown, Pa
Darron, I think Kevin said wrap the knock sensor several times with tape was not for leaking but to make it a little less sensitive.

Dug out my old 1999 GM Perf Parts catalog that has all the parts and parts number for the HO 350 into the 82-87 Camaro that had either the LG4 or the L69 305. That was a complete engine and all the other parts necessary to make that engine swap an emissions legal install 20 years ago into that Camaro. It was a big deal back then.
Anyhow parts used, ECM 1228079, PROM 24502456 (zz4 PROM), Knock sensor 10456288, ESC module 16128261
That module is available through Rock or others.
From what I found the 305 and 350 modules are different, would think input frequency sensitivity would be the difference.

The old batch retard timing retard was all they had back then. Not a bad system for the day but today's individual cyl retard is so much better.

I do believe if you disconnect the Knock sensor at the sensor the ECM doesn't see a voltage drop and will not set a 43 or retard timing.
The ECM really doesn't have a limp home mode in the CCC ECM. But it may retard timing until the code 43 is cleared from the ECM. Bitflipper, Dylan may be able to enlighten us on that.

When I ran the 427 SBC on CCC for a few months a Safeguard processor was used. It controls dwell, rev limiter and did individual cyl timing retard. The ESC was still powered up and sending 7.5 vdc to the ECM but the knock sensor was disconnected. A sensor for the 4 1/8" bore was used and the signal sent to the Safeguard. The ECM never set a 43 code.
Bob

#1067245 - 07/12/20 05:17 AM Re: Code 43 [Re: 1988SS]  
Joined: May 2000
Posts: 1,716
BadSS Offline
20+ Year
BadSS  Offline
20+ Year
Member

Joined: May 2000
Posts: 1,716
Pearl, MS, 39208
Yes, Bob is correct on the tape. Back in the day, I found I could get the 305 knock sensor to work "OK" with the swapped in 350s without having to do any changes. I see on my previous post I left off the 406 part. On the 406s I had to wrap the threads of the sensor with as much teflon tape as I could and only tighten it just enough in order to desensitize it. Doing that allowed the computer and knock sensor to work well enough together.

I knew the 305 TPIs had different knock sensors and ESCs than the 350s. I also figured that there probably was some differences in the chip. However, I had no issue running the 305 knock sensor and ESC when I swapped over to a 355. I used the stock 305 BIN to make program changes in the chip and all ran just fine - no retard issues.

After finding that the 86 305 chip was "buggy" I used a BIN from a 1989 350 and moved all the program changes over. I remember having increased knock retard afterwards and ended up having to do some adjustments in that area after the swap to keep timing from being pulled. So I'm thinking the 350 chips had a little different programming that probably wasn't part of the hack (areas of things we could view with the app)

So, now that I think more about it, I'm not sure swapping to a 350 knock sensor and ESC and not having the ZZ4 chip/module Bob mentioned (along with the other part numbers) would be a good idea. Other's might be able to say for sure. However, I know with 100% certainty you will have no issues with a stock 305 knock sensor (wrapped with a little teflon tape) and the stock 305 ESC with a 355 engine.

#1067250 - 07/12/20 02:35 PM Re: Code 43 [Re: 1988SS]  
Joined: Jan 2000
Posts: 4,865
mmc427ss Online content
20+ Year
mmc427ss  Online Content
20+ Year
Member

Joined: Jan 2000
Posts: 4,865
Pottstown, Pa
You can actually test the sensitivity of the knock sensor. With the engine running at above 850 rpm and the car on jackstand and running at 20 mph, engine temp up to normal so ECM is in closed loop you can tap on the block in the area of the knock sensor and see if rpm drops. This per Helm s service manual. You can also back probe the Black wire at the ESC module and read voltage drop there. Normal voltage at the C terminal, Black wire, is 7.5 volts when no knock is sensed. Voltage output to ECM drops when knock is sensed.
Another thing, make sure the knock sensor wire that runs to the ESC is not near a spark plug wire, that may influence the knock sensor signal.
Bob

#1067255 - 07/12/20 05:03 PM Re: Code 43 [Re: 1988SS]  
Joined: May 2007
Posts: 89
1988SS Offline
10+ Year
1988SS  Offline
10+ Year
Member

Joined: May 2007
Posts: 89
Georgetown, TX
Wow....you guys are wealth of knowledge....wish you were closer and I'd buy you a steak dinner and your favorite beverage to look my car over.

I have changed the ESC to the 350 version. Guess I'll switch the knock sensor to a 350 just to make sure that is what's is in there. I shouldn't need to drain the oil to switch out the knock sensor...correct?

I'm running a ADS Super Chip, which has been in the car since 1989. Any thoughts on that chip? ....or should I look into the 24502456 (ZZ4) ?

Thanks for your input!

Darron

Last edited by 1988SS; 07/12/20 05:17 PM.

1988 Monte Carlo SS
#1067261 - 07/12/20 10:58 PM Re: Code 43 [Re: 1988SS]  
Joined: May 2000
Posts: 1,716
BadSS Offline
20+ Year
BadSS  Offline
20+ Year
Member

Joined: May 2000
Posts: 1,716
Pearl, MS, 39208
Knock sensor is in the block's coolant passage. I've been able to swap out a knock sensor without draining the coolant. Feet toward the rear of the car on your right side, pan under the sensor, loosen the sensor until you can turn it by hand. Have the new one ready and easy to access. Loosen the old one with the right hand and be prepared to put your left hand thumb over the hole once you have the old one out. Take the new one and quickly "plug the hole" with it and screw in. Engine will need to be cold and the radiator cap removed. There should be no pressure - just a gravity drain. It will be a little messy, need eye protection. Or you could just get the car high enough to get a clean bucket under it and take out the sensor and let the coolant drain out. I say clean bucket because once drained it will be a good bit of coolant, but you can put all but the last few ounces (usually have some sentiment) of the coolant back in the engine.

Most of those aftermarket chips are snake-oil and many back then did little to nothing - especially on the later models. Most required the timing to be set to stock (6-degrees). If you still have the stock chip, I'd put that one back in and bump the timing to 10-degrees if you run premium gas. If not, double check your base timing and make sure it's not over 6-degrees with that after-market chip - see below for setting timing
https://montecarloss.com/SS_FAQ_10.html

Since you have the 350 ESC, I'd get the 350 knock sensor and see how it worked. If you still have an issue, I'd think the ZZ4 chip would be your best bet to run the 350 ESC and 350 knock sensor. Second best bet would be stock 305 chip, 305 ESC, and 305 knock sensor.

#1067262 - 07/13/20 12:22 AM Re: Code 43 [Re: 1988SS]  
Joined: Jan 2000
Posts: 4,865
mmc427ss Online content
20+ Year
mmc427ss  Online Content
20+ Year
Member

Joined: Jan 2000
Posts: 4,865
Pottstown, Pa
Same here, installed a Hyperchip in the 86 ECM way back in like 1993, all I think I got was aggressive timing and the engine was more knock prone. even running premium regularly and a can of GM Top Engine Cleaner dumped down the carb a couple times a year to clean the piston tops. That chip has been sitting in the original box since 1994.

The 88 SS got the 8079 ECM which is a slightly faster ECM than the ones used 86 and older. So you already have the best ECM for a carbed CCC.
The ZZ4 PROM has been long gone, every once in a while one will appear on Ebay in trade for your first born. Bitflipper was able to burn several ZZ4 PROM replica but says the necessary unprogrammed E-PROM is even hard to find today and expensive. He may have one to sell yet. The ZZ4 PROM primarily eliminated EGR function, but had slightly more aggressive timing curve.

My 86 though not running CCC anymore has the 079 and GM ZZ4 PROM still tucked away in the kick panel.

If you still have the 88 SS PROM stashed away somewhere I would try swapping it back in. Dial in the 10 degrees and test drive. I always found the rattle on the old 305 was when it shifted 1 to 2, low rpm, and getting onto the throttle, loading the engine.

Texas in the Summer is hot, make sure the cooling system is up to snuff. I ran 180 thermostats, shooting for max of high 180s when the A/C is cranking. A/C working well on a hot day, effects rad temps a lot.
Bob

#1067276 - 07/13/20 04:03 PM Re: Code 43 [Re: 1988SS]  
Joined: Jun 2004
Posts: 357
Bitflipper Online content
15+ Year
Bitflipper  Online Content
15+ Year
Member

Joined: Jun 2004
Posts: 357
Las Vegas, NV
There are only a few Hybrid ZZ4/L69 EPROMs remaining in my box. Get one while I still have one available. Price goes up after that and may take considerably longer to ship.


[Linked Image]
#1067278 - 07/13/20 05:08 PM Re: Code 43 [Re: Bitflipper]  
Joined: May 2007
Posts: 89
1988SS Offline
10+ Year
1988SS  Offline
10+ Year
Member

Joined: May 2007
Posts: 89
Georgetown, TX
Originally Posted by Bitflipper
There are only a few Hybrid ZZ4/L69 EPROMs remaining in my box. Get one while I still have one available. Price goes up after that and may take considerably longer to ship.

Trying to send you a PM but get message that your in-box is full. I'm interested in getting one from you. Please contact me.

Thanks,
Darron

Last edited by 1988SS; 07/13/20 05:15 PM.

1988 Monte Carlo SS
#1067280 - 07/13/20 05:43 PM Re: Code 43 [Re: 1988SS]  
Joined: Jun 2004
Posts: 357
Bitflipper Online content
15+ Year
Bitflipper  Online Content
15+ Year
Member

Joined: Jun 2004
Posts: 357
Las Vegas, NV
PM sent.


[Linked Image]

Random Images
737/thumbs/small_DSC00316.jpg
by McNamee
500/thumbs/MCSS4.jpg
by Wrathchild
500/thumbs/SD530544.JPG
by pearl83SS
500/thumbs/87_Monte2.jpg
by mightymonte10
500/thumbs/Photo_4.JPG
by Chief Jimbo
Help MonteCarloSS.com


Recent Contributors
finallySS
Authorized Vendors
Tell them you saw it
on MonteCarloSS.com!


CustomMonteSSParts.com
Dixie Monte Carlo Depot
GSI Interiors
HRpartsNstuff
Mikes Montes
Savitske Classic & Custom
Powered by UBB.threads™ PHP Forum Software 7.6.0