Toyota corolla 2013 1.3 manual pick problem

[pwuser161876220137]

Hello everyone,

I bought a 2013 Toyota Corolla 1.3 with a manual transmission a few months ago, but I'm dealing with a recurring problem. After driving the car for approximately 10 to 15 kilometers, I notice a significant drop in its performance.

In the morning, when I initially start the car, everything seems fine, the acceleration is smooth and the pick is perfect. But as I drive a bit, the car's pick drops significantly. It even struggles to gain speed in 2nd gear at around 15 kmph, and sometimes I have to shift down to 1st gear just to get going. Also, when this happens after driving a bit, the fuel consumption goes from 14 15 to 7 8.

Here's what my mechanic and I have tried so far:

• Replaced the fuel pump multiple times, now installed a bigger fuel pump and the fuel pressure is at 60.
• Changed to genuine Toyota spark plugs bought from the official Toyota dealership.
• Replaced the ignition coils to ensure there are no issues with spark leakage or misfires.
• Replaced the oxygen sensor.
• Replaced the accelerator pedal.
• Even did an engine overhaul due to its slight weakness and oil consumption, thinking it might help the power issue, but sadly, it's still there.

I've been trying to fix this power problem for the last 2 to 3 months and came to a dead end.
I'd really appreciate any suggestions or possible solutions that you may have so that I can explore them further.

Thank you for your help guys.

[Xulfiqar]

Is your maf sensor providing accurate input?

[pwuser161876220137]

I think we have not checked the MAF sensor input, but there is no error coming up on scan. I'll get the MAF sensor checked and see if there is any issue. Thanks for pointing it out.

[smartdevil_striker]

MAF sensor check kren

[Xulfiqar]

Dont just look for error codes, you need to see if the maf sensor is actually working as it should.

[smartdevil_striker]

Sir how to check MAF sensor working perfectly or not when there is no code, any symptoms?

[Xulfiqar]

You check with an oscope, you need to see its reaction to sudden air change.

If you have an actual toyota techstream and genuine mongoose cable (fast refresh rate) you can see some quick pid movement, but its easy with a dso.

[supraman2jz]

Damn you overhauled your engine for this? It's usually a MAF or O2 problem when your car performs sluggish at operating temps.

[Xulfiqar]

Ustaad needed a payday.

[engnr.mubashir]

He got overhauling done on basis on oil consumption history.

[pwuser161876220137]

Thanks to all for your suggestions, here is an update.

I replaced the MAF sensor, but unfortunately, it didn't resolve the power issue. Also the readings on MAF sensor at different RPMs were the same as those checked in another Corolla.

Today, my electrician checked the engine's pressure. I found that three of the cylinders are at approximately 150, while one cylinder is at around 125. Could this one cylinder with 125 pressure be causing the power problem and what is the solution? And does it mean that engine overhaul is not done correctly?

Additionally, my electrician suggested that after the engine overhaul, the piston size might not be correctly adjusted, especially since the car has only been driven 3000 KM after the overhaul. He mentioned that pistons tend to adjust their size after covering around 10,000 KM due to the effects of heat and friction. He advised me to drive the car for a few thousand more kilometers to allow the pistons to adjust.

Any thoughts on these statements? And any other suggestions?

Note: Electrician who told me all this and the Mechanic who overhauled the engine do not know each other. So, there is no reason to suspect that he is attempting to cover up any faults on the mechanic's part.

[supraman2jz]

1- Your electrician should be capable of understanding MAF readings, simply because another Corolla had the same readings does not validate yours as working fine. I have found most cars in Pakistan have had their MAF and O2 tampered by soaking them in wd40, carb cleaners or other chemicals which kills the sensors slowly.

2- The low comp reading on that one cylinder could mean weak rings, a stuck valve or bad valve seals. What this number means is compression is leaking out of that cylinder. One cyl with a bad compression will not cause a sudden loss of power like you are facing.

3- There are no variable piston sizes if the bore is on standard. Even if your mechanic used oversized pistons after a cyl hone, your pistons don't seat to the cyl. Your piston rings seat to the cyl and that is what the initial run-in period of ~1000 kms does. You don't need 10,000kms for the rings to seat in.

4- You really need to show your car to someone who is qualified in trouble shooting this and not a tukka ustaad..

[supraman2jz]

Did your car ever had cng installed in it?

[Xulfiqar]

Pistons adjust their size? Please tell me this is a joke!

Your new built engine has 150 psi compression? And 125 on one cylinder?

Was this overhaul done Allah tawakkal with free scrap parts??

Honestly I think you have been had!! Your series of events tell a scam story or your mechanic has zero working knowledge and is only good for oil changes at maximum.

[kamranakram1000]

What should be the psi compression?

I'll consult with some other mechanic to get it fixed or should I go with engine replacement?

@supraman2jz no, cng was never installed.

[Xulfiqar]

You should be at 200 psi compression pressure, 150 psi is absolute lower limit and 125 psi is “nearly dead cylinder zone”

[engnr.mubashir]

Brother you are victim of desi jugar ustaad feeling sorry for you and your loss.
Kindly don’t waste more money on anything looks like ustaad just wrongly overhauled the engine of your car. Debate ends full stop.
BTW if piston any days requires any adjustments according to temperature change then it would done it within 500 kms.

And how much did you paid for the overhaul job.

[sleeper]

Run away from both of these useless of mechanic and electrician who have robbed you and will continue because you dont know how to resolve the issue neither those idiots.

What's ur location, so the we can advise who u can visit single time for correct rectification

[kamranakram1000]

I kinda have same feelings about being a victim. @engnr.mubashir I paid 55K for engine overhaul. Well, lets just move on from this.

If necessary, I'm ready to replace the engine with a good kabli one.

@sleeper Please suggest some good mechanic in Multan or nearby areas like DG Khan, Bahawalpur, Vehari, Khanewal, etc.

[supraman2jz]

I don't think your mechanic ever overhauled your motor. Xulfiqar above pointed to a very valid point, your engine should not have 150 psi across (mostly) on a freshly rebuilt engine. A weak and tired 2nzfe shows 130-150psi. A strong motor should be 200+. Either you got duped, or whoever was checking compression did not know what he was doing or was using faulty equipment.

Well, lets just move on from this.
If necessary, I'm ready to replace the engine with a good kabli one.

I would say, get a 2nd opinion on your compression. Visit someone legible and get another compression test done. At worst, you'd waste 500-1000rs for the test. But if you find better comp numbers, you probably won't need a new engine. If not, just get a new assembly and call it a day.