Bosch Super RO 488 plugs for M103? - PeachParts Mercedes-Benz Forum

tilac1 · #1 05-13-2010, 07:35 PM

Are the plugs in my '88 W124 the correct? If not I'd like to find the correct non-resister NGK plug. Anyone know a source?

tjts1 · #2 05-13-2010, 07:47 PM

Quote:

Originally Posted by tilac1

Are the plugs in my '88 W124 the correct? If not I'd like to find the correct non-resister NGK plug. Anyone know a source?

Why non resistor? I used NGK TR5 which came out to $2 each.
http://www.ngksparkplugs.com/part_finder/car_truck_suv/results.asp?engineid=30015

tilac1 · #3 05-14-2010, 04:59 AM

I've read that the M103 was designed to use non-resistor plug but it seems no one stocks them anymore. I've always been very pleased with NGK plugs.

Cal Learner · #4 05-14-2010, 09:49 AM

BP5EFS or BP6EFS for slightly cooler plug (highway driving). Until recently, I heard that Fastlane Phil stocked them. That may no longer be the case. Also, the MB Classic Center in Irvine apparently stocks the correct NGK plugs, and I can still get the correct Bosch H9DC0 at my local MB dealer. HTH

Duner · #5 05-14-2010, 10:56 PM

This info is from the archives so may or may not be correct. M103 originally
has non resister wire but had a resistor in each plug connector and non-resistor plugs.
At some point the big thinks decided to use resistor plugs and non resistor plug connectors and non resistor wire. So the answer to your question might be decided by what wire set you have. If what I said is not correct I would like to know what is correct.

tjts1 · #6 05-14-2010, 11:18 PM

Quote:

Originally Posted by Duner

This info is from the archives so may or may not be correct. M103 originally
has non resister wire but had a resistor in each plug connector and non-resistor plugs.
At some point the big thinks decided to use resistor plugs and non resistor plug connectors and non resistor wire. So the answer to your question might be decided by what wire set you have. If what I said is not correct I would like to know what is correct.

This makes sense. AFIK its very hard to find non resistor plugs these these days.

This might help. NGK spark plug code

The following spark plugs are specified for the M103
TR5
TR5GP
ITR5F13
TR5IX
So find one of these without the "R" in the name and you should be good.

JamesDean · #7 05-15-2010, 01:13 AM

Denso T20EP-U or T16EP-U

Cal Learner · #8 05-15-2010, 07:37 AM

Quote:

Originally Posted by tjts1

This makes sense. AFIK its very hard to find non resistor plugs these these days.

The following spark plugs are specified for the M103
TR5
TR5GP
ITR5F13
TR5IX
So find one of these without the "R" in the name and you should be good.

The model numbers I gave in my earlier post are the correct NGK plugs for the M103 engine. As for sources, it's true that you cannot just stroll into your local auto parts store and find the correct copper core non-resistor plugs. But there are lots of M103 motors in operation still, and we're finding plugs for them. It's worth trying the places I listed earlier. In addition to those sources, I know that there are several I-net vendors in the UK that stock these plugs and can fill orders within a week.

tilac1 · #9 05-16-2010, 08:50 AM

Where to find? ******** has 'em but shipped from the UK. Anywhere in US?

Cal Learner · #10 05-16-2010, 09:49 AM

Quote:

Originally Posted by tilac1

Where to find? ******** has 'em but shipped from the UK. Anywhere in US?

?? You're looking for something closer than the several suggestions already made, including the ******** you yourself mentioned? Maybe, like your next door neighbor?

tilac1 · #11 05-16-2010, 09:55 AM

Very funny. I've looked and found no US sources. Why pay int'l shipping? Don't be a dick.

JamesDean · #12 06-05-2010, 07:05 PM

Quote:

Originally Posted by tilac1

Very funny. I've looked and found no US sources. Why pay int'l shipping? Don't be a dick.

Which plugs are you looking for in the US specifically?

6x T20EPU's shipped to me for $11.29
http://www.********.com/catalog/raframecatalog.php?catalog=14&partnum=5031&a=FR14-5031-356

Additionally you wouldnt try to cramp a Intel Core i7 into that Apple II would you?

Use the correct part for your car and it will love you long time.

tjts1 · #13 06-05-2010, 09:05 PM

Quote:

Originally Posted by JamesDean

Additionally you wouldnt try to cramp a Intel Core i7 into that Apple II would you?

Why the hell not?

http://gizmodo.com/5159104/mac-mini-inside-an-apple-disk-ii-case

It sounds like most people on here have no clue what the resistor does. It is completely irrelevant if the resistor is in the plug or wires or both. Just make sure at least 1 of the components has one.

Ivanerrol · #14 06-05-2010, 10:02 PM

Quote:

Originally Posted by tjts1

Why the hell not?

It sounds like most people on here have no clue what the resistor does. It is completely irrelevant if the resistor is in the plug or wires or both. Just make sure at least 1 of the components has one.

M.B. spent vast amounts of development dollars on their engines. I'm sure they know what they are doing with the specified components.

Not only do the leads have a 1Kohm resistance in the plug ends, the distributor cap also has resistance built in.

The original idea for have resistance in the leads was for suppression of interference for the vehicle electronic components - the ECU, OVP, FPR and even the radio. The EZL is a very delicate component that can be damaged just by losing the thermal paste holding it down to the fender.

M103 engines are getting over twenty years old. We see all sorts of posts in threads complaining about idling problems and performance problems for M103 engines. The plugs are part of the problems here.
M.B. have stated that resistor type plugs can be used (times have marched on - they have also specified plastic oil can be used, it was never available back in the days when the engine was designed).
Do not put wire only non resistive leads on the engine. If you can't source non resistor type NGK's just put resistor type in - leave the leads alone. Only use OEM or Beru leads, distributor cap and rotor.

Note that platinum, multi posted plugs and other exotic plugs have been known to cause idling problems in M103 engines (over time). Ordinary $1.50 NGK non resistance plugs should last a very long time. Putting $15.00 plugs into an engine that doesn't require it is a waste of money especially when they start playing up after a relatively short life.

Everyone knows that computers are fickle machines that require nice environments to keep optimal operation going. Laptops only lasts a few years because of the wear and tear and knocks they get. Normal computers are subject to the vagaries of power flucuatuions and spikes - that's why we have power filters, surge suppressors and U.P.S's.

Modern cars are computer controlled gadgets. Vehicle E.C.U.'s are subject to all sorts of weather conditions and to the vagaries of alternators, regulators and uneven power supply. There are many filters and associated electronic circuitry the manufacturers install in the vehicles to protect the E.C.U.s and other electronic control equipment.

JamesDean · #15 06-05-2010, 10:31 PM

Quote:

Originally Posted by tjts1

Why the hell not?

It sounds like most people on here have no clue what the resistor does. It is completely irrelevant if the resistor is in the plug or wires or both. Just make sure at least 1 of the components has one.

Well..not that you wouldnt want to buy you couldnt, as the apple ii wouldnt be able to interface with it and thus you would have wasted money on it.

Resistance is very important in electrical circuits. more of it is not a good idea especially in the case of the ignition system. The system was designed with a known value of resistance..adding to that would effect overall performance and longevity of all parts concerned.

On the topic of the platinum/irridium/etc types. My mechanic says they never ran well in these older cars. I'd never use them.