Pinging with EAT chip...'94 525iT

[rizal]

I live in San Diego, have a '94 525iT with 127K miles, put an EAT chip in it several motnhs ago. Runs very nicely. However, even on 91 octane, I get light pinging on light throttle, which cleans up well with more throttle. How much is OK? Should there be zero? Any way to diagnose whether this is causing harm?
Thanks very much. Al

[MarkD]

I live in San Diego, have a '94 525iT with 127K miles, put an EAT chip in it several motnhs ago. Runs very nicely. However, even on 91 octane, I get light pinging on light throttle, which cleans up well with more throttle. How much is OK? Should there be zero? Any way to diagnose whether this is causing harm?
Thanks very much. Al

In general, ping is not good. but a small rpm range such as 2200 to 2600 at light load (throttle) isn't going to destroy your motor. For some reason, there are a certain number of m50tu's that have a tendency to ping, and some even do it with a stock chip. I've got a feeling that it is caused by the MAF going a bit out of spec. (and making the motor run a bit lean).

The cars that ping like yours does also do it with Dinan and Conforti chips.
I am hopind o make a new version just for cars that have this problem. I did make a test version for someone in CA (Phil Lau) who has not posted here in at least a year, and he said it helped quite a bit.

MarkD

[RobPatt]

Rizal, can tell you I've had the EAT for the last about 30K miles on a '93 525i w/the same engine as you and DO experience a minor ping (or some other rattling) in the same RPM range under light acceleration. I always run Chevron or Shell highoctane. But can also say Mark is right, this has been well discussed on the forum here, and most of us w/this engine experience the same thing. Personally I don't know if it's pinging, think it is. Most of us do our own maint and run Mobil 1 0w40 (is this relevent?)

Mark, I'd be willing to test a prototype if you like. ( I bought your EAT about 3 years ago during a Christmas special you were running ).

Keep the EAT and remember to give it a good drive on the highway every now and then, and use good clean quality gas, eliminate vaccuum leaks etc.


....maybe we've all got a little vaccuum leak in the same hose in the same place (under the intake mani?) and we all just don't know it? Small enough not to throw any error codes, but enough to ping under a different engine mapping? Who knows.

still happy,
Rob.

[Bill R.]

slight buildup on the thin film or thick film depending on which type it is , which causes it to run slightly lean and ping under low throttle application , Cleaning the air intake side of the maf using throttle body cleaner takes care of the problem. Throttle body cleaner not carb cleaner. Carb cleaner can damage a thick or thin film sensor. On the fords and chevies that this is most predominant on it takes care of the problem and clears up the slight hesitation that usually goes hand in hand with this.




In general, ping is not good. but a small rpm range such as 2200 to 2600 at light load (throttle) isn't going to destroy your motor. For some reason, there are a certain number of m50tu's that have a tendency to ping, and some even do it with a stock chip. I've got a feeling that it is caused by the MAF going a bit out of spec. (and making the motor run a bit lean).

The cars that ping like yours does also do it with Dinan and Conforti chips.
I am hopind o make a new version just for cars that have this problem. I did make a test version for someone in CA (Phil Lau) who has not posted here in at least a year, and he said it helped quite a bit.

MarkD

[rizal]

Thanks very, very much for the sage responses. Much better than I expected.
Mark, I too would be interested in trialing one of your revised chips if you're interested.

Thanks again. Al

[Trevor]

I got one of the first OZ EAT chips from MArk and had the intermittant pinging after 1-2 weeks of use.
Recently I have put the ccip back in and on 91 octane the pinging was painful.
Filled up yesterday with 95 octane and the problem has almost gone.
Fingers crossed.

[Anthony (M5 in Calgary)]

slight buildup on the thin film or thick film depending on which type it is , which causes it to run slightly lean and ping under low throttle application , Cleaning the air intake side of the maf using throttle body cleaner takes care of the problem. Throttle body cleaner not carb cleaner. Carb cleaner can damage a thick or thin film sensor. On the fords and chevies that this is most predominant on it takes care of the problem and clears up the slight hesitation that usually goes hand in hand with this.


Bill, would you do the same cleaning to a hot wire MAF like the one on my M5? Any tips?

[kev535i]

I got one of the first OZ EAT chips from MArk and had the intermittant pinging after 1-2 weeks of use.
Recently I have put the ccip back in and on 91 octane the pinging was painful.
Filled up yesterday with 95 octane and the problem has almost gone.
Fingers crossed.
I recently had this conversation with Mark - to convert US octane to Aus octane you just add 4 ie 91 US = 95 Aus. Eat chips are designed to run on premium unleaded 95 or greater in Aus . you should try 98 and you will really appriecate the chip
http://www.users.bigpond.com/kevinfishing/beach.jpg

[grave77]

I would say the same ... lower octane cause more pinging, I bought mine few monthes ago from e-bay and I use 98 octane and it runs excellant, while I think Mark made it on octane 95. it's for Mark to comment about the 98 octane as BigKriss also use 98 octane on EAT Chip.

[ryan roopnarine]

count me in as one of the US people that has knock on US premium (93 AKI) with their EAT. before i developed my vacuum leak (when i had my engine in extraordinarily good condition), i had the ping around the 2k area. i have a slight hunt in idle right now, so i will refrain from speaking about running condition right now. i think its somewhat disingenuous for some (not Mark) to suggest the US users up their fuel octane to fix the issue. the lowest octane that can be sold as "premium" in the us is 91 aki, or 95 RON. problem with that is that almost NO ONE sells 91aki, premium in the US now generally is 93 aki or slightly higher (97 or 98 RON). the grades sold here are (RON): 87, 89 or (91-93) premium. mark tells us to use "premium unleaded only", which everyone does.

someone asked about the hot-wire cleaning. i have the hot wire MAF (not the hot film maf like vanos m50s have), and i clean it with contact cleaner periodically. i have a PS leak which, i think is creating an oil spray underhood, and contaminating it slightly, as no matter how much i clean it, a "oily" looking residue remains, i can see the rainbow when the wire is still wetted.

[MarkD]

I got one of the first OZ EAT chips from MArk and had the intermittant pinging after 1-2 weeks of use.
Recently I have put the ccip back in and on 91 octane the pinging was painful.
Filled up yesterday with 95 octane and the problem has almost gone.
Fingers crossed.

91 AKI as used in USA/CAnada is 95 RON.

Mark

[Jon K]

I occasionally clean my hot wire maf. Use maf safe cleaner it burns it off in about 5 seconds upon shut off. As for pinging running 91... why not run 92 or 93?

[rizal]

I occasionally clean my hot wire maf. Use maf safe cleaner it burns it off in about 5 seconds upon shut off. As for pinging running 91... why not run 92 or 93?
You can't get >91 in California, or at least not in San Diego.

[Suede]

Here in California the highest octane premium you can buy is 91.
I put an EAT chip in my 1990 535 manual. I had significant pinging at 3000 through 3500 rpm, worse with ac on or hot day. Car has 120,000 miles and has had all scheduled maintenance, and then some. Runs perfect with stock or EAT chip, gets almost 25 mpg on the highway at 80 mph.
I replaced plugs, wires, coils, ran techron, did some Italian tuneups, but couldn't get rid of the pinging.
I had to take the chip out, and am now awaiting Mark D's detuned California gas version.
Any other anti ping measures I should be taking?

Suede

[Russell]

I generally use Chevron or Shell V-power 93 octane gas. Not sure it makes any difference. Just my experience.

[grave77]

we no longer have the RON 91 and below ... I couldn'd try it to know how it would be. I think also the M50 Engine is more affected by the gas type with pinging. but still I have noticed good results when comparing unleaded RON 95 with RON 98 ... RON 98 worked perfectly. with the heated wire thingy ... if it's mass was changed due to dust hitting it or sand dust like in our area I think cleaning wont help up. I would not recommend oil sprays ... tuner or video head cleaners r better since they completely dry off and will not allow any dust to stick on later.

[rizal]

slight buildup on the thin film or thick film depending on which type it is , which causes it to run slightly lean and ping under low throttle application , Cleaning the air intake side of the maf using throttle body cleaner takes care of the problem. Throttle body cleaner not carb cleaner. Carb cleaner can damage a thick or thin film sensor. On the fords and chevies that this is most predominant on it takes care of the problem and clears up the slight hesitation that usually goes hand in hand with this.

I checked into products for this and saw one by Gum-Out for fuel injected cars but it said NOT to spray it across the MAF sensor. So how exaclty would you recommend it be applied safely? Thanks.

[brillantrot]

In MarkD's defense, my M50TU has a Turner/Conforti chip, and it pings in these RPM ranges as well. I plan on following Bill R's. advice and cleaning the MAF tomorrow, along with an oil change. Hopefully it clears things up.

[RobPatt]

...more of an engine thing than a chip thing...esp w/ur reference to the turner/conforti chip...

[rizal]

...more of an engine thing than a chip thing...esp w/ur reference to the turner/conforti chip...
Thanks for the responses. I noticed on a can of Gum-Out throttle body cleaner for fuel injected engines that it says to NOT spray across the MAF sensor. So, what exactly is it that needs to be cleaned? everything EXCEPT the MAF sensor? Does anyone have any pictures by chance? Thanks once again.

[rizal]

Thanks for the responses. I noticed on a can of Gum-Out throttle body cleaner for fuel injected engines that it says to NOT spray across the MAF sensor. So, what exactly is it that needs to be cleaned? everything EXCEPT the MAF sensor? Does anyone have any pictures by chance? Thanks once again.

01/2006 update:
Replaced the O2 sensor on a hunch, as it was apparently the original; first owner seems to have failed to replace it at 60,000 miles, now has 131,000. Symptoms included the slight pinging when warmed up, ran more strongly and responsivley w/out pinging when the engine was cold. Interesting; In 11/05, it passed CA smog testing (specialized smog center, full test, on the rollers, not a tailpipe only test) with the EAT chip and the bad O2 sensor, but just barely. With the new sensor, day and night...runs as strongly & crisply when warmed up as when cold, and no discernible pinging when warm. I'll follow the mileage to check for imporvements, but I was already getting 19 mpg in town and 25-27 on the highway at approx 75 mph with A/C. Haven't tried cleaning the MAF yet. FYI to others. Thanks for all the input. Al

[Jay 535i]

FWIW, after buying my '95 Audi S6 (which my wife killed) I cleaned the MAF with brake cleaner. The improvement was astonishing.