Talking about cars in violation of regulations: Diagnosis and treatment of stubborn diseases of throttle alarm

  10
 September 7, 2024
I believe that many students, especially those who love cars for more than 6 years, have encountered such a bad thing: throttle alarm.
This is the fault light: Xiaoman has a lightning on his waist! I was screwed by this thing.

1. Painful experience:

First, the company’s car made this problem, tossing about for a long time, until the car was returned to the company, it was not finally solved. See: https://www.xcar.com.cn/bbs/viewthread.php?tid=32799129
Later, it was my own. When the car was about 7 years old, it began to appear occasionally, and then it appeared more and more frequently, because it was irregular (in fact, I didn’t feel the law at first) and appeared intermittently, and it was always said on the Internet that it had been added to crooked oil, so I thought it was a problem of oil:
Https://www.xcar.com.cn/bbs/viewthread.php?tid=91203700
After that, the frequency is getting higher and higher, and it also depends on Sinopec’s No. 95, so it can’t blame the gas station.

In retrospect, it is possible that the gas station has been wronged

Many students think the same as me, and the car mechanic is the same: since the throttle alarm, then from the throttle to find fault! The first thing that comes to mind is, of course, cleaning the throttle!

Burning geese is of no use to eggs!

It may be better for a few days after washing, but it will soon revive and the fault will recur! By the way, the throttle of an ordinary car is dirtier, there is no problem, and it doesn’t need to be cleaned frequently.

Then change the throttle seal gasket:

Burning geese is not of any use to eggs!

Whether the fault light should be on or on!

Finally, one morning in 2020, after the fault light was on, there was no response to stepping on the throttle, and the throttle stopped moving at all! At this point, I am a little happy: I can finally change the throttle, and finally say goodbye to the pesky throttle fault light!

So, several hundred changed the throttle of the original factory!

Just after the change, it was really easy for a while, and I didn’t worry anymore!

However, the good times did not last long, more than two thousand kilometers after the change of the throttle, the lights were on again with double TMD!

You really fooled me this time! TM has changed to a brand new original factory-made accessories, what else do you want me to do?

Second, find the cause.

Check on the computer, the fault code is: detected high air flow / vacuum leakage (slow accumulation)
The car repairman told me to change the air Flowmeter. I don’t think it’s that simple! He focused on the word “air flow”, while I paid attention to “vacuum leakage”.

Various searches on the Internet, found a car friend’s post, saying that the air intake tube pad is aging, look at his analysis, it is very reasonable, and the situation is also similar to what I encountered:
1. The age of the car is over 6 years.
two。 Most of them occur in the start-up or idle stage of cold cars.
3. There is more winter than summer.
4. The fault disappeared after the hot car.

Analysis of the reason: due to the resistance of the air filter, the external air can not reach the air intake system smoothly, and a certain degree of vacuum will be formed in the air intake path when the engine is inhaled. The driving computer relies on this vacuum degree to allocate the air intake. If the vacuum degree is abnormal for some reason, the computer can not correctly judge, it will cause the intake system to work in disorder, and the computer will give an alarm:

Engine system schematic diagram

Schematic diagram of air intake system

Intake manifold
The intake manifold (branch) is the last node where the combustion air enters the engine. If there is air leakage here, the intake vacuum will appear the so-called “leakage”. Between the intake manifold and the engine intake, the gasket is sealed by a rubber intake manifold gasket. The gasket is in a state of high temperature for a long time, and it will generally age, harden or even crack after 6 years, resulting in air leakage.

III. Symptomatic treatment

I thought the above analysis was reliable, so I bought the intake manifold gasket to replace it.

Due to the previous “repeated attacks”, after the replacement can only be “run to see”, now in the past month, ran more than a thousand kilometers, the fault light has not been on again.

I hope it is completely solved this time!

IV. Complaint and reflection

This engine design of Nima Jeep (Mitsubishi) is really TM (why blame Mitsubishi? Because the urban SUV series of Jeep is the product of cooperation with Mitsubishi, and the power part is Mitsubishi) the layout is too unreasonable to facilitate maintenance. In order to change such a gasket of several tens of yuan, the water pipes and pipes were dismantled and tossed about for several hours. What broke my heart even more was that I spent several hundred to change the long-lasting antifreeze (ten years) of Mopar that I had just changed to let the car repair boy give it to me and replaced it with ordinary antifreeze.
In reflection, the failure of solar terms is probably not a cause but a result: vacuum leakage leads to excessive action of the throttle and damage.

V. Summary

If your car also has throttle alarm problems, in line with the above-mentioned basic characteristics: the car is more than 6 years old, often occurs in the cold car start-up or idle stage, winter is more than summer, and the fault disappears after hot car. Basically can consider this problem, if there is the same fault code, then basically fit, change it!