Hi I have a honda civic lsi 1993 model. I have a problem with the car when I go the store or somewere. Its starts up fine and drives brill but leaving the car off for a few moments going to put gas in or etc it has a problem starting up again. When I crank it you can hear the fuel pump turn and engine light comes on for 2 secounds then goes off but there's been once or twice were the engine light has stayed on when it won't start but everything sounds fine but won't start and then when I leave for a about 5-10 minutes it will start again and it feels like it never happened. I've had the car for 3 months my sister sold me the car which she had for 2 years but she had never had no problem. I've had the car serviced 2 months ago this problem has only started a few weeks ago had timing belt,water pump,spark plugs and oil changed could it be the main relay or ecm that's cause of the problem. I've read on this site that these are the main problems with hondas. Please can you help me out on what this problem can be because it is driving me up the wall and I can't rely on this car at the moment :cool:

Car has done 66000 miles (uk milage)

The ECM is likely failing. Perform the K-Test on the ECM, when the CEL stays on. I would start shopping around for the best deal you can find on a rebult ECM. I know they can be pretty expensive in the UK.

Here's how to replace it yourself:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-3.html#post235038

Long-term, you also want to replace the Ignition Control Module, coil, and main relay. Once you do this, you will have restored the reliability you are looking for. If you do the work yourself, it won't cost a lot of money.

Were is th ecm located? What if I order the ecm from the usa because I have checked prices I can't seem to come across one in the uk they all from the usa even with main relay I have to order will it matter with it being a uk model

This should help you locate and replace the ECM:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-3.html#post235038

Obtain the Honda Part No. off your current ECM and buy an exact replacement. I've worked with some chaps in the UK and there can be problems, if your Civic has an immobilizer system. If your's doesn't, you will likely be OK.

Is the ecm located under the drivers or passenger side I'm not sure if american models are the same as uk models? uk drivers position is on the right. Il try to perform the k test,are the MAP sensors located next to ecm?were is the service connecter terminals and how do you jump this with a paper clip?if I have 5 volts between d19 and d21 how do I repair this reference wire to map sensor? Plaese can you help me.

Yes, the ECM should be located on the passenger's side. MAP Sensor is located on the firewall--look for the hose going to the throttle body. Don't worry about performing the confirming test (D19 and D21).

Can you tell me how much would I look at buying a new ECM rough idea? I also went to the autoshop today I can buy most of the things like,ignition coil,fuel pump etc but the ECM and main relay I need to get the part number for both of them and I can't get a price util I retrevie part no for both

Do you have any images on ECM and map sensors would be very grateful, cheers

No.

I will get back to you in a weeks time once the car has been installed with new parts

ECM AND ECU are they the same thing? Because when I look for ECM it comes up as ECM ECU ON EBAY

Are ecm and ecu the same thing because on eBay it comes up as ecm ecu

Same.

Can I use ecu or ecm and main relay imported from the usa if it is the same product

Can't say for certain--need to check part numbers. Always some risk.

When the ecu is replaced does it need reprogramming or it a straight replacement?

Should be straight replacement, unless there is an immobilizer system. If you have an immobilizer, the original ECM needs to be remanufactured.

It does have a immobilizer system and when you say the original ecu needs to be remanufactured what do you mean by this?

You need to send your present ECM to an outfit in the UK and have them rebuild it, if it is bad. It will likely be very expensive (1,200 pounds or more), so do your homework and shop around. You never said your ECM failed the K-Test, so maybe your ECM is fine.

I will perform the k test this week as my car is parked in my friends garage but what if the ECM is OK then what's the other possibility would it be the main relay,igniter coil ordistributer needs replacing

Here's my standard advice:

When you turn the ignition switch to ON (not START), does the Check Engine Light (CEL) come on and then go off after 2 seconds? If not, the problem is with the ACG (ALT) (S) fuse, in the underdash fuse/relay box; ECM (perform the K-Test); Main Relay; or the Ignition Switch. Perform tests in that order.

Since your Civic's CEL stays on at times, the ECM may be in the process of failing. I would also clean the main ECM ground, located on the thermostat housing. Unfortunately, my experience in these situations is that the ECM is breaking down and is no longer reliable.

The ignitor and coil has nothing to do with the CEL staying on, so you can rule those out.

Hi there I have discovered that it isn't the ecm that is the problem it is the main relay because I drove the car it started up fine the main relay and fuel pump turnd over for 2 secounds which was OK but I went to the shop come back after 2 minutes turned the ignition to number 2 can't hear the main relay turn so I will inspect the main relay see if can it be repaired or order a new one I will get back to you

To me, it sounds like intermittent ECM failure, which proceeds total failure. I don't think replacing the main relay will solve the primary problem at all. When the ECM is not working (cause), neither will the main relay (effect). I understand your denial, because ECMs are expensive.