How to deter the popular problem of hot start in Honda cars?


Posted by: Oluwaseun Adeniji

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You just come back from the grocery store and realize your Honda car is stubborn to start, you just can't find an answer for this though the car is new. Believe it or not, many Honda users share these popular issues that we call hot start problems. How to deter them from happening, check out this article now!

1. What is hot start problem in Honda cars?

Well. You could say that this start reluctance could be as a result of main relay problem. Usually, Honda has an infamous reputation for encountering issues with restarting right after sitting a hot engine for just few minutes, which we call hot start problems. This could happen to you when you decide to pick up something from the grocery store after filling your tank or several other instances that would make you power down your engine for some minutes.


Used Honda cars often have difficulties in starting when the engine runs hot

2. How to detect the problem? - Main relay testing

When the main relay has an issue, you would likely experience this trouble. The main relay is the device that electronically ensures the opening and closing of supply of fuel to the car engine. In order to know if you are truly having this problem, take a look at these steps here on Naijauto.

  • You need to hold the linkage of the throttle with a piece of paper at a position, which is set. You need to also set the speed of the engine to rpm of about 2500.
  • Allow the engine to run with the hood closed for as much as 20 minutes.
  • Turn off the engine after removing the wire off the throttle.
  • Allow it to be seated for few minutes. Afterwards, try and restart it.
  • When the engine fails to come up, put the ignition key on. Usually, check engine light should come up for some seconds and fade off. This is when you will also hear the running of fuel pump for like 2 secs. You would hear the clicking sounds of the main relay after the light had gone out.
  • If you fail to hear any clicking sound coming from the main relay, you should take a look at the fuel pump or main relay to check power and also the terminal eight for possible ground connection. When there is an adequate terminal eight or ground connection and you notice there is no power, this could indicate a bad main relay.

Video: How to identify a bad main relay on a Honda (PGM-FI)

>>> If you happen to drive a Pilot, this post is exactly made for you: Simple tips to maintain used Honda Pilot

3. Consequences of a bad main relay

Many at times, the problems are similar but different models of Honda have their peculiar problems especially when there is a bad main relay. If you are driving a Honda Accord, the sign is always a loss of fuel pressure. For those with Civic, power will be lost to fuel pump and injector. But it is also possible for you not to lose the fuel pump due to difficulty of fuel injector opening without power. So, when you have a bad main relay and there is the absence of fuel injector's voltage, a message (code 16 computer) would be set for the injector. The reason mainly could be due to lack of voltage reading from the computer on the injector’s ground side.

4. What you should know before the main relay replacement

When you are absolutely sure that the main reason for this problem is from main relay, carry out a relay test specifically for Honda products to be certain. There is no worse feeling than wasting time and money on a costly part, only to discover that it is not even the cause of the problem.


When the main relay is faulty, it poses a big problem starting your car engine while it is still hot

You should remember that you are might not be lucky enough to get a return policy especially on any electrical component from your supplier or auto shop. So, you need to be really sure what you are diving into.

5. Other possible reasons for hot start problems

Before you rush into it, you need to know that, there are few other reasons why you might experience a start problem while the engine is hot. It could be as a result of the bad igniter, bad ignition coil or bad ignition switch. You might need to carry out a simple spark test. You could also decide to perform test on the coil too. It is often difficult to carry out tests on the igniter since you would need to get your hand on automotive oscilloscope, which might not have at home.

When the main relay malfunctions, it will present to you signs similar to a bad igniter or coil. When it is hot weather, it is most likely going to fail. This symptom will be many at times exhibited by other reasons. It is also possible that a difficult start comes first before you experience a bad main relay. There is definitely no point for you to panic over this as you could still start the engine despite the difficulty you have might have experienced momentarily. You should allow the car to cool down when you feel the problem might be due to the failed igniter or coil.


Nothing feels better than driving your Honda without fear of not starting

Final notes

When you are patient enough and up to the task, you could save yourself few bucks by replacing that main relay on your own. If not, it is advisable you take your car to the nearest mechanic workshop to avoid further damage.

>>> Plenty of car maintenance tips and advice always available on for your reference. Check them out!

Oluwaseun Adeniji
Oluwaseun Adeniji

Oluwaseun Adeniji

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Oluwaseun Adeniji is a passionate writer and a poet with special interest in writing about cars. He is a master degree holder in international conflict and management. He enjoys feeding the public with the latest auto gist and well researched car reviews. He is also a strong football lover. So, if Oluwaseun is not writing, expect him to be reading about sports.

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