Auto-LPG and sparkplugs...

[ghosthunter]

I have noticed with some of our cars equipped with SGI-AutoLPG.

The cars with SGI Auto-LPG systems have a tendency to "wear out" sparkplugs resulting in uneven idle, power loss or even engine stalling.

The vehicles are:

Honda City 1.3L DSi
Ford Expedition
Mazda 3 1.6L

I am not sure if the tuning (lean) is the fault or simply the use of LPG itself (which is said to have a hotter ignition temperature than gasoline).

As for potential solutions, using platinum tipped sparkplugs seems to be the leading solution in the web.

Has anyone else have similar experiences?

[n5110]

my emulator kit was installed last aug 08. last month i check the condition of my sparkplugs (http://tsikot.yehey.com/forums/showt...29208&page=150) color brown and looks normal naman. im still using the stock plugs. will check again bukas siguro before heading to tagaytay.

will the platinum tipped plugs also improve the FC? magkano ba ito? thanks.

[ghosthunter]

my emulator kit was installed last aug 08. last month i check the condition of my sparkplugs (http://tsikot.yehey.com/forums/showt...29208&page=150) color brown and looks normal naman. im still using the stock plugs. will check again bukas siguro before heading to tagaytay.

emulator/venturi kits seems to be immune to such problems since they are usually tuned to run richer which results in a cooler combusion temperature.

will the platinum tipped plugs also improve the FC? magkano ba ito? thanks.

IMHO, no. They just last longer especially in higher performance engines. Usually cost 1.5 to three times the price of ordinary sparkplugs.

[Mile2]

Just checked my spark plugs yesterday and they are still okay, with only white powdery stains and no burn out signs.

BTW, the spark plugs now runs 10,000++ kms on LPG (Denso Iridium IKH22 one step colder)

My previous stock plugs (Denso K20HR-U11) on LPG seems to have burn out ground tips even less than 5,000 kms.

[vinj]

So far i have no such experiences with the Altis and when i changed plugs, my old plugs were clean and were worn normally. What i did though was to change to platinum tipped plugs with a one-step higher heat range since the LPG burns hotter then regular unleaded; i'm using NGK BKR6E platinums (vs. the normal BKR5E or it's Denso equivalent). They don't cost much more then regular copper plugs as well.

[Mile2]

So far i have no such experiences with the Altis and when i changed plugs, my old plugs were clean and were worn normally. What i did though was to change to platinum tipped plugs with a one-step higher heat range since the LPG burns hotter then regular unleaded; i'm using NGK BKR6E platinums (vs. the normal BKR5E or it's Denso equivalent). They don't cost much more then regular copper plugs as well.

I think BKR6E is one step colder. For Japanese manufacturers (NGK, Denso), the higher the number, the colder the plug.

[vernieg]

Nakakita na ako ng Bosch platinum spark plugs on a daily driven taxi na after six months of using lpg sira na ang negative electrode ng spark plug due to acidic type of corrosion. Same thing will happen to upper cylinder block over time, mas mauna nga lang ang spark plug. Such corrosion did not happened to gasoline engines. It is a fuel combustion by product issue and not a fuel-air mixture issue.

Ask an experienced mekaniko or visit their shop, those who have serviced cars running lpg, they will tell you the real story about cars using lpg. Other than health problems experienced by taxi drivers using lpg, this corrosion issue is a big problem for car owners.

Fortunately, nag sulpotan na ngayon ang mga spark plugs for LPG use.

example:
http://www.bosch.com.au/content/language1/html/6578.htm


Unfortunately, the upper cylinder block replacement ay hindi madali mahanap unless daming surplus na pumapasok. Kahit meron mang supply ng upper cylinder block, it is not still practical to have it replaced from time to time.

Did anyone question about the quality of lpg fuel used for cars here in our country? I hope someone will.

I have noticed with some of our cars equipped with SGI-AutoLPG.

The cars with SGI Auto-LPG systems have a tendency to "wear out" sparkplugs resulting in uneven idle, power loss or even engine stalling.

[ghosthunter]

Nakakita na ako ng Bosch platinum spark plugs on a daily driven taxi na after six months of using lpg sira na ang negative electrode ng spark plug due to acidic type of corrosion. Same thing will happen to upper cylinder block over time, mas mauna nga lang ang spark plug. Such corrosion did not happened to gasoline engines. It is a fuel combustion by product issue and not a fuel-air mixture issue.

Ask an experienced mekaniko or visit their shop, those who have serviced cars running lpg, they will tell you the real story about cars using lpg. Other than health problems experienced by taxi drivers using lpg, this corrosion issue is a big problem for car owners.

I am still more convinced that the so-called corrosion is actually pitting caused by detonation due to improper air/fuel mixtures. Richer mixtures should prevent this.

BTW, lean air-fuel mixtures does generate more NOx which results in higher than normal nitric acid during combustion. Given that taxi drivers have a bad habit of adjusting their LPG systems to running leaner than normal, I would not be surprised if taxi units encounter this problem more than privately owned cars.