Cylinder Head Temp Sensor
#1
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Cylinder Head Temp Sensor
A few weeks ago I did a bunch of work on a good friends 93RSA, and while replacing the cyl head temp sensor, I found the connector to be really discolored. Has anyone else found this to be the case? This car has 108K miles on her.
Also found the real reason why his car was running like crap, a crumbling dizzy belt. He paid A LOT of money to a shop in Santa Monica (not TRE) for them to fix his poor running car. $800+ later, he got a valve adjustment, air filter, oil and oil filter, fuel filter and new spark plugs installed. Car still runs like crap, but this shop says all is well.. Receipt even says they adjusted the timing..WTF?PUHLLEEEEEZ!
Even better, this same shop a year earlier was paid to have this dizzy belt replaced 20K miles ago. Huh, funny...I removed the dizzy only to find the factory swaged pin that retains the gear, still there.. Crooks!!!
So, at the last minute, Hergesheimers had a belt in stock. I installed it, car runs like new!!
Also found the real reason why his car was running like crap, a crumbling dizzy belt. He paid A LOT of money to a shop in Santa Monica (not TRE) for them to fix his poor running car. $800+ later, he got a valve adjustment, air filter, oil and oil filter, fuel filter and new spark plugs installed. Car still runs like crap, but this shop says all is well.. Receipt even says they adjusted the timing..WTF?PUHLLEEEEEZ!
Even better, this same shop a year earlier was paid to have this dizzy belt replaced 20K miles ago. Huh, funny...I removed the dizzy only to find the factory swaged pin that retains the gear, still there.. Crooks!!!
So, at the last minute, Hergesheimers had a belt in stock. I installed it, car runs like new!!
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All the more reason I try to do all the work on my own car.
Guess it's much easier and profitable for them to write down that they did the work than, heaven forbid, actually doing it, huh?
Good catch, Chris... ever think of moving to Hawaii? I could use a friend like you when major maintenance starts popping up
Guess it's much easier and profitable for them to write down that they did the work than, heaven forbid, actually doing it, huh?
Good catch, Chris... ever think of moving to Hawaii? I could use a friend like you when major maintenance starts popping up
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Originally Posted by kkim
All the more reason I try to do all the work on my own car.
Guess it's much easier and profitable for them to write down that they did the work than, heaven forbid, actually doing it, huh?
Good catch, Chris... ever think of moving to Hawaii? I could use a friend like you when major maintenance starts popping up
Guess it's much easier and profitable for them to write down that they did the work than, heaven forbid, actually doing it, huh?
Good catch, Chris... ever think of moving to Hawaii? I could use a friend like you when major maintenance starts popping up
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Originally Posted by chris walrod
MMMMMMM, Hawaaaaiiiiiiiii.... I need
Mahalo, brah!!
#6
Chris, I was wondering if you could get a temp readout from the cylinder head temp sensor? If it is a standard J-type or K-type thermocouple you could do some interesting tests with a small multi-channel data logger. For example, test to see what difference the rear engine tray has on cylinder head temperature with respect to ambient temperature.
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Yes one could do just that. A simple data logger and a thermocouple placed on a cylinder head. Or, one on each bank.. Would be interesting data!
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#8
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Originally Posted by chris walrod
I found the connector to be really discolored. Has anyone else found this to be the case? This car has 108K miles on her.
Originally Posted by chris walrod
Even better, this same shop a year earlier was paid to have this dizzy belt replaced 20K miles ago. Huh, funny...I removed the dizzy only to find the factory swaged pin that retains the gear, still there.. Crooks!!!
Originally Posted by Blaine S
I was wondering if you could get a temp readout from the cylinder head temp sensor?
0'C = 4.4 - 6.8 kOhms
15 - 30'C = 1.4 - 3.6 kOhms
40'C = 1-1.3 kOhms
80C = 250 - 390 Ohms
100C = 160 - 210 Ohms
Somewhere on a computer here I have the data curve that the ECU uses, if you want it let me know and I will look for it.
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No markings on the white plastic connector, just a logo of some sort 'S' over 'W', or 'M' over 'S'. Not sure really. I wouldnt think UV light exposure is the culprit as the portion of the connector that is discolored, is what is coverered when connected. ???
The solid pin that secured the drive gear had three, very symetrical swagings on it, markings by a machine no doubt.. This belt had more than 20K miles on it.
The solid pin that secured the drive gear had three, very symetrical swagings on it, markings by a machine no doubt.. This belt had more than 20K miles on it.
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Originally Posted by chris walrod
I wouldnt think UV light exposure is the culprit as the portion of the connector that is discolored, is what is coverered when connected. ???
Originally Posted by chris walrod
This belt had more than 20K miles on it.
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I didnt, but the owner of the car did. He went back with this failed dizzy belt and stated his case of paying good money for them to fix his car, and didnt receive a fixed car. Manager or owner, not sure who, had a, according to my friend, really embarassed look about him. This shop person offered absolutely nothing in return.
As far as the discolored connector, could be staining from the other end of the weatherpack-type seal. I'll have to pull my connector off to have a look on my 993. Now I am curious
As far as the discolored connector, could be staining from the other end of the weatherpack-type seal. I'll have to pull my connector off to have a look on my 993. Now I am curious
#12
"I still really wonder how/why so much of the Porsche aftermarket can still exist after all these years." - JasonAndreas -
Obviously there's nowhere near the Porsche repair business now as there was
20 years ago here in SoCal (one of the largest if not the largest) Porsche markets
worldwide. Although, an increasing number of shops have closed over the last few
years, many still are strong because most older (out of warranty) Porsches are
serviced by independents. The reasons are:
1. preceived/real cost savings or value
2. more personalized service
3. experience with previous Porsche cars
There are always a few questionable shops, but these few are greatly out numbered
by the real quality ones. What was mentioned on this thread is more the exception
than the riule.
"Somewhere on a computer here I have the data curve that the ECU uses" - JasonAndreas -
Once the CHT drops below about 350 ohms, the CHT no longer affects fuel mixture.
So, one can always eliminate/isolate the CHT by shorting it out with a jumper.
Obviously there's nowhere near the Porsche repair business now as there was
20 years ago here in SoCal (one of the largest if not the largest) Porsche markets
worldwide. Although, an increasing number of shops have closed over the last few
years, many still are strong because most older (out of warranty) Porsches are
serviced by independents. The reasons are:
1. preceived/real cost savings or value
2. more personalized service
3. experience with previous Porsche cars
There are always a few questionable shops, but these few are greatly out numbered
by the real quality ones. What was mentioned on this thread is more the exception
than the riule.
"Somewhere on a computer here I have the data curve that the ECU uses" - JasonAndreas -
Once the CHT drops below about 350 ohms, the CHT no longer affects fuel mixture.
So, one can always eliminate/isolate the CHT by shorting it out with a jumper.
#13
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Good post, Chris!
Two things come to mind:
1. One should do as much work on one's own car as one can, even if it "seems" harder than you're accustomed to. Taken with patience and good advice, most maintenance can be done by yourself.
2. Once you find a trustworthy and skilled mechanic/shop, build a relationship with them. Don't shop the "cheapest" price because the trust and skill you have found in that establishment is worth every dollar to both you and your car.
Edward
Two things come to mind:
1. One should do as much work on one's own car as one can, even if it "seems" harder than you're accustomed to. Taken with patience and good advice, most maintenance can be done by yourself.
2. Once you find a trustworthy and skilled mechanic/shop, build a relationship with them. Don't shop the "cheapest" price because the trust and skill you have found in that establishment is worth every dollar to both you and your car.
Edward
#14
Cylinder Head Temp - acceptable range?
I just installed a Supercharger kit on my 993 engine. After doing some research I got the impression that it will be critical to monitor the CHT, in particular because I am not running an intercooler (for the time being). So, I installed a CHT sensor (plug ring type).
I wonder what's the normal operating range for CHT. I would like to get an idea of what should be the temp under normal driving, and also under spirited driving (as in DE events). And, clearly, what would be the STOP IT NOW, level.
So far I have only driven the car a few miles on the road after the installation of the SC and the CHT rteading is between 250-300F.
Thanks for you inputs
I wonder what's the normal operating range for CHT. I would like to get an idea of what should be the temp under normal driving, and also under spirited driving (as in DE events). And, clearly, what would be the STOP IT NOW, level.
So far I have only driven the car a few miles on the road after the installation of the SC and the CHT rteading is between 250-300F.
Thanks for you inputs