Cam shaft error and long starts

[syedfaizan1]

hey guys i am getting wierd issue in corolla 2nzfe 2012 .

car takes too long self to get start even sometimes 2 3 self and get camshaft position sensor error. i replaced the sensor last week but again got the error and car still takes lone 2 3 self to start. sometimes it keep taking the self and dont start and then I switch on off the ignition then it gets start.

its ecotec cng version but its disconnected
timing chain replaced already with vvti gear

i don't know what causes long selfs plugs are new, thoratel is cleaned few days back, everything was cleaned too. but all 4 coils are covered with tape.

please suggest how tl resolve this issue.

change the fuel pump?
Changw the coils?

using oil 20w50
car avg 10 km per liter

@Xulfiqar can you help in some suggestions

[haseeb.basharat]

please suggest how tl resolve this issue.

change the fuel pump?Changw the coils?

Most probably fuel filter gone bad.
Change fuel filter and its element. Cost a mere 1500rs only. If your car is starting then fuel pump is working. There is some restriction that's not letting the fuel to flow freely. So, change the fuel filter.

[xenerking]

did u check timing chain to be as spec?

replaced gears having same teeth as original?

cam sensor verified? kabuli can also turn out to be bad

[Xulfiqar]

Can you connect a scan tool to check cam sensor rpm? You should ideally use a scope to check it.

Is the cam sensor error for missing signal or cam timing mismatch. The cam timing fault after a timing job is due to not unlocking the vvt gear while and not using a torque wrench to tighten it.

If you are getting a lost signal error then its a case of bad sensor or broken wiring or even cng advancer issues, I think the factory installed cng injector kit from toyota uses the cam sensor for timing advance.

[uzeemujeeb]

i think you have recently changed the VVTI set up. Was it a brand new item or from scrap , it seems either it is not timed correctly or gone bad again.

[syedfaizan1]

i am also feeling this sicne it has same issue sicne i bought the car. i will check the cng button wiring connection and chnage the pump initially and see the results

[syedfaizan1]

yes the gears and chain were of same car and specs were same of jenyan

[syedfaizan1]

i have obd scanner.will check the reading from it

actually this issue was there before the timing chain job was done. either the cam shaft is faulty inside or maybe the fuel pump is bad or may be the cng button which i never used cause some issue . will check from the electrician for the button and at first will replace the pump

the cng kit is disconnected from the head of car and all pipes are also disconnected which can interfere in car performance. the manifold is also covered with pipes and stop any vaccum leaks properly.

i will check the results today and show you. car don't hesitate while running but its just starting issue.

[syedfaizan1]

the chain and its parts were brand new and the pulley vtti gear was qabli from shafiq more.

this problem was also there before this timing chain work. i had replaced both sensors crank and cam.

it seems like the fuel pump pressure is bad or some wiring issue thats holding the signals

[xenerking]

U can verify fuel pressure by attaching a guage before going for replacement directly

[syedfaizan1]

okay and my all coils have tapped on them. does it make any issues?

[uzeemujeeb]

start with replacing fuel filter in pump then check for fuel pressure in injector rail at key click, ignition ON 1st , then at cranking the engine.

@xulfiqar saheb @syncview can guide for more diagnostics.

[syedfaizan1]

sure bro am also feeling of bad fuel pump. even in my office the new corollas got bad fuel pump this is 8 years old abused owner car so i am sure it might have bad fuel pump that is always drive on low petrol or kacha bad afghani petrol lol

but more points will be helpful when I will go to mechanic will look after everything one by one.
the mechanic is of my same age. young guy. does what ever i say

[uzeemujeeb]

sir if you are in Karachi i'd recommend Mr. Irshad Ahmed 0300 223 7538, Jamil Autos almost 2 years ago i got my indus corolla overhauled by him. Allah has been kind the vehicle is running trouble free. few other family members are referred there and all are happy. I suggest please try him.

[uzeemujeeb]

the mechanic is of my same age. young guy. does what ever i say

you have edge over him, you are better educated and you are a PakWheeler

[syedfaizan1]

yes yes i know them but never been to them except one during lockdown or us me shop bund thi. they are far from my home thars why couldn't get to them easily. its around 15 km away from my home but now i am thinking to visit them. how much they charge for diagnosis?

[uzeemujeeb]

true that you can dial and ask him for charges, that will be better because of your distance.

few of family members visit him from Malir falcon colony and now Mr. Irshad is their regular mechanic

[syedfaizan1]

just talked with irshad bhai. he suggested to chnage fuel pump 1st and then see.

[syedfaizan1]

update.

guys I changed the fuel pump today but issue is still there and now getting cam shaft position sensor error and crankshaft position sensor error after very long self. though I chnaged both sensors last month.

[syedfaizan1]

@xulfiqar @haseeb.basharat @xenerking @hash4u what could be the possible cause for these errors and what shall i check now. do you guys think the ecu may be faulty or the inner cam or crankshaft are faulty in real?