Hard Starting on CNG

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Hard Starting on CNG

Hi guys,

One of my friends has got a Tartarini CNG Kit installed in his Toyota Corolla 1995. The car starts well on petrol but it requires 7-9 cranks when being started on CNG. This only happens if the car is being started after more than 5 hours have past since last engine shut off eg in the morning or when leaving workplace. It starts well even on cng when the engine shut off n start have lesser interval in between. Another friend has the same problem in his brand new company fitted Coure and no mechanic could fix it even the fancy mech engineer of Toyota Indus Khi. My guess is that CNG reaches the combustion chamber a bit late after considerable time has lapsed since last shut off. Plz comment.

Gari.pk User 936 asked on 18 Jun 2010 13:07:23 pm

1 Answer

359 views |

Samar - on 18 Jun 2010 13:07:37 pm

hello!!!
yeah...this can be the possible reason but main reason behind this is that CNG Methane has difficult to pass spark out of it so that it can burn...and creates less power than petrol....so u need 1st of all strong spark to ignite it.....all yours ignition system must be in fine condition in order to run ur car fine on CNG.....check igniiton coil...if weaks change it with heavy duty one.....always reduce spark plug gap from 0.8mm(default) to 0.6mm...this can make it start ur car quicker.....check wires if weaken so replace the plug wires....with high tension ones....
on morning it need some hard starting but if starts then it goes normally on 1 normal self.....or 2.....suggestion for morning is that always convert car on petrol at night......start on petrol in morning then convert on CNG....the easiest and safest way...and when kicking in key....always press and release accelerator...not full but with slightly pressure.....
Thanxxx