4G93P Hiccups!

[haiyoweiya]

Good morning to all guys and girls in ZTH.

Am currently driving Wira with 4G93P engine (from Eterna) + 1.5 cable operated manual gearbox.

The car drives fine albeit the high fuel consumption (full tank RON 95 approx. RM 60 = 260km).

Recently I went up to Cameron Highlands with family and I was all the way maintaining 140 km/h until about to reach Tapah exit, my car started to have very mild hiccups. The hiccups could be felt even by just maintaining the acceleration. Whenever I try to accelerate further, the hiccup is more apparent and the vehicle speed would hardly go up.

The hiccup gradually worsen as I drove further. I took my way up from Simpang Pulai exit and during the hill climb, the hiccup was so worse that I have to stop at the road side. Popped up the bonnet and did a visual check around the engine bay, nothing abnormal was noticed. Then I pulled the accelerator cable to rev up the engine, the wider the throttle opens, the worse the hiccup was. If I slowly increase the engine rev (by pulling the accelerator cable), engine speed did climbed but mild hiccup could be felt on the engine. But if I gave it a wide open throttle, the engine speed drops instead of going up! An audible growl could be heard (more when WOT) from the intake side as if the engine is surging for air. :stupid:

Kinda pointless at that moment, I switched off the ignition just thinking that maybe that would reset the engine ECU memory. Then I fired up the engine again, and noticed that the problem seemed to be gone. I could rev up the engine freely. So I continued my journey up to CH thinking that the problem had gone away.

But the longer I drive the car, the hiccup appears again, from mild to apparent. So each and every time I have to stop by the road side to restart the engine again just to get rid of the hiccups. It was very annoying as I couldn't overtake any cars (embarrassing la~ ), because even though I restarted the engine, it would not perform perfectly, the hiccup was still there (very mild).

I noticed this problem to appear after very long journey drive. This is my daily drive car which I travel from Klang to PJ everyday, and proven nothing wrong with 20+km a trip. But once it drives in long distance, the problem arises.

Has anyone of y'all encountered this problem before? I know the MMC throttle body is very problematic and I doubt it's either the throttle body or the air flow meter. :hmmmm:

Would like to hear from any sifus here to provide me some precious advise.

Thank you very much in advance!

 

[haiyoweiya]

No one here encounters the same symptom? zzzZZZzzz...

 

[Ratbit]

From my opinion , it seems like exhaust emission is not exiting smoothly..this usually happen to cars that had swap their engine to a higher power engine, or a turbo engine, without changing the size and setting of their exhaust piping,
so when u high rev the engine :vroam:, exhaust emission unable to get out fast enough, thus creating an internal pressure, which hinder the engine to operate smoothly.

 

[DanzEterna]

have u checked your spark plugs & plug cable & fuel filter lately?

 

[haiyoweiya]

From my opinion , it seems like exhaust emission is not exiting smoothly..this usually happen to cars that had swap their engine to a higher power engine, or a turbo engine, without changing the size and setting of their exhaust piping,
so when u high rev the engine :vroam:, exhaust emission unable to get out fast enough, thus creating an internal pressure, which hinder the engine to operate smoothly.

Hello Ratbit,

Your idea might sounds true but the fact is, it happens only after I drive it for more than... say 60 km or so. Even driving from Klang to PJ/KL the engine performs nicely and revs happily without a single hiccup. And by turning off the engine and restart it, indeed it has some minor improvement (lesser hiccup) but will gradually increase if I continue to drive it. In order to get rid of it, I will have to park my car and let the engine cool down totally, then it's all good to go.

I really have great doubts towards the oxygen sensors, air flow meter or the throttle body. Anyway is the throttle body serviceable/repairable? Bcoz the stepper motor seems to going south soon as when every time I turn on the ignition, a scratching sound could be heard from the throttle body. I was told that this is the sign/symptom of throttle body failure. A new one is quite costly, around RM 800, Mikuni made in Japan. :stupid:

---------- Post added at 10:27 AM ---------- 6 hour anti-bump limit - Previous post was at 10:24 AM ----------

have u checked your spark plugs & plug cable & fuel filter lately?

Hello DanzEterna,

My spark plugs are quite new, just changed recently to Denso Iridium IK20. Plug cables are stock though. Fuel filter was also changed last year. :)

 

[haiyoweiya]

Greetings!

Any idea come across during the weekend? Anyone care to share?

Cheers... :)

 

[joe_mirage]

check ur fuel pump =) .. give it a try. last time i encountered that kind of problem too.

 

[karem]

yes, if fuel pump is ok then maybe injector also... these 2 play along with the air flow sensor.

 

[xtremeleo]

sounds like ignition related, borrow a set of plug cables from a fren and install them. take ur time to drive for sum distances, and see if the problem still occur. how long was it dat u last changed the plugs+cables btw?

 

[mydvdrom]

many causes. i got this problem and all of the below items contributed to it. lolz. that's wad i get for leaving the car unused for 3-4yrs.

1. spark plugs
2. plug cables
3. injectors
4. fuel pump
5. rusty fuel tank
6. dirty fuel piping and fuel rail (can be cleaned with by blowing air)
7. ignitor

ur problem sounds more like sparks or fuel is insufficient. i know the feeling like not enuff fuel is entering the combustion or the engine is running on 2 cylinders and not 4. try checking on the items above 1 by 1. a good workshop should be able to help u.

 

[haiyoweiya]

check ur fuel pump =) .. give it a try. last time i encountered that kind of problem too.

Hello Joe,

So what did you do to eliminate the problem? You replaced the fuel pump? How much it cost you? TQ! :)

---------- Post added at 12:05 PM ---------- 6 hour anti-bump limit - Previous post was at 11:56 AM ----------

yes, if fuel pump is ok then maybe injector also... these 2 play along with the air flow sensor.

Hello Karem,

If injector is the culprit, wouldn't it be a permanent fault? I doubt more towards the fuel pump as it has motor pumping the fuel, hence when it heats up, it fails gradually. Is this logical? :hmmmm:

Thanks anyway!

---------- Post added at 12:13 PM ---------- 6 hour anti-bump limit - Previous post was at 12:05 PM ----------

sounds like ignition related, borrow a set of plug cables from a fren and install them. take ur time to drive for sum distances, and see if the problem still occur. how long was it dat u last changed the plugs+cables btw?

Hi xtremeleo,

My plug cables are still stock standard. The plugs were replaced last year, I think around 15,000 km ago if not mistaken.

Anyway is it possible to find back its original plug cable and fuel pump? Otherwise what would you recommend? I don't quite trust the scrapped parts at kedai potong though.

Cheers! :proud:

---------- Post added at 12:20 PM ---------- 6 hour anti-bump limit - Previous post was at 12:13 PM ----------

many causes. i got this problem and all of the below items contributed to it. lolz. that's wad i get for leaving the car unused for 3-4yrs.

1. spark plugs
2. plug cables
3. injectors
4. fuel pump
5. rusty fuel tank
6. dirty fuel piping and fuel rail (can be cleaned with by blowing air)
7. ignitor

ur problem sounds more like sparks or fuel is insufficient. i know the feeling like not enuff fuel is entering the combustion or the engine is running on 2 cylinders and not 4. try checking on the items above 1 by 1. a good workshop should be able to help u.

Hello mydvdrom,

Where is this ignitor located at?

The sensation of the hiccup was like as if the engine is surging for fuel. The more I rev the engine, the more tendency it tends to pull back the rev. So if I rev (in neutral) slowly and gently, the rev rises (but with very mild jerking). But it has no impact when the engine is idling though.

Just imagine going uphill like at Cameron or Genting, really a nightmare! Scared the shit out of me!

Cheers!

 

[xtremeleo]

My plug cables are still stock standard. The plugs were replaced last year, I think around 15,000 km ago if not mistaken.

Anyway is it possible to find back its original plug cable and fuel pump? Otherwise what would you recommend? I don't quite trust the scrapped parts at kedai potong though.

Cheers!

yes, it is possible to get new of those stuffs sir, no problemo. from ur new info, dont go changing anything just yet..

The sensation of the hiccup was like as if the engine is surging for fuel. The more I rev the engine, the more tendency it tends to pull back the rev. So if I rev (in neutral) slowly and gently, the rev rises (but with very mild jerking). But it has no impact when the engine is idling though.

the problem sounds familiar, have u ever suffer from rusty fuel tank before? its an easy check

 

[haiyoweiya]

yes, it is possible to get new of those stuffs sir, no problemo. from ur new info, dont go changing anything just yet..



the problem sounds familiar, have u ever suffer from rusty fuel tank before? its an easy check

Hi there,

You mean spare part shops do sell these things?

About the fuel tank, do I need to strip down the whole tank for rust inspection?

TQ~ :)

 

[xtremeleo]

yes sir, they defnitely do sell those items.

as for the fuel tank, initially u just have to take the pump out and take a look at the filter jer. if there are signs of rust on there, flash a light into the tank and see how bad it is. if its bad, most of the time u cant repair it and need a new tank. good luck sir, u can pm me for more details

---------- Post added at 02:33 PM ---------- 6 hour anti-bump limit - Previous post was at 02:24 PM ----------

yes sir, they defnitely do sell those items.

as for the fuel tank, initially u just have to take the pump out and take a look at the filter jer. if there are signs of rust on there, flash a light into the tank and see how bad it is. if its bad, most of the time u cant repair it and need a new tank. good luck sir, u can pm me for more details

 

[haiyoweiya]

yes sir, they defnitely do sell those items.

as for the fuel tank, initially u just have to take the pump out and take a look at the filter jer. if there are signs of rust on there, flash a light into the tank and see how bad it is. if its bad, most of the time u cant repair it and need a new tank. good luck sir, u can pm me for more details

---------- Post added at 02:33 PM ---------- 6 hour anti-bump limit - Previous post was at 02:24 PM ----------

yes sir, they defnitely do sell those items.

as for the fuel tank, initially u just have to take the pump out and take a look at the filter jer. if there are signs of rust on there, flash a light into the tank and see how bad it is. if its bad, most of the time u cant repair it and need a new tank. good luck sir, u can pm me for more details

Good morning mate,

Point noted. Will check it out sooner. THX! :proud:

Other than the above suggestions, any other ideas from ZTH members?

Cheers!