Relay Location
 

I am working on a 93 Mazda 626, 4cyl, 2.0, A code engine. 144000 miles. Does anyone know the correct location of the ECM Relay on this car. It is not in the engine compartment fuse box. Thanks

RE: Relay Location
 

The ECM relay is in the main fuse block under the hood. There call it the MAIN relay. It's located between the STARTER CUT and the
FUEL PUMP relays. To left there should be an empty relay connection, unless the vehicle is for CANADA.

RE: Relay Location
 

Thank you very much.

RE: Relay Location
 

Here is the problem I have had and am unable to solve. The car started and ran for about 5 miles and was towed into a garage. They replaced the distributor with a rebuilt unit. Then it happened again about 2 days later. It was taken back to the garage and another rebuilt unit was installed. Then the problem happened again and they brought the car to me. I checked the system and installed a brand new dist. I have 35-40 lbs of fuel pressure when cranking, the node lights are lighting and the injector resistance is as it should be. I cleaned and tested the IAC solenoid. I tested the cam and crank sensor circuits, coil primary and secondary resistance and voltage. The timing is right on, and I have good spark at the plugs and the compression is 190, 190, 190, and 120. I have tested the relays and the ignition switch and all the fuses. The only code set is a code 8 and I found that the mass air flow sensor was bad. I am going to replace it, but I don't think this will prevent the car from starting. I have reached my level of ability to diagnose on this car. I am leaning toward saying the PCM may be bad but I realise that once you buy one, you own it and I don't want to cost the owner money that he doesn't need to spend. Is there anything that I may have overlooked on this car. Any help would be appreciated.******* Here is an update if anyone is interested. I replaced the MAF sensor with a rebuilt one, pulled the plugs and dried them and blew out the cylinders. The car started but it really ran bad and I have a serious overfueling condition. Black smoke.

RE: Relay Location
 

Any body reading this?

RE: Relay Location
 

STAN: Have you checked the fuel pressure regulator diaphram for leaking? Just disconnect the vacuum hose to see if you have fuel
dripping out the regulator port.

RE: Relay Location
 

Yes I did that when I first checked the fuel pressure. When I disconnected the vac hose it was dry, however this was when the engine was still running good. Maybe I need to check it again. I am also going to disassemble and recheck the IAC solenoid again. I cleaned it once, but it might be sticking since I cleaned it.

RE: Relay Location
 

OK here is an update. I replaced the maf sensor, cleaned the IAC but still no start. I checked the Fuel Pressure regulator vac line and it was wet but not dripping. I also checked the fuel pressure regulator solenoid IAW the instructions in the Haynes manual and the solenoid works exactly opposite of the way Haynes describes. Haynes says with no power applied to solenoid i should be able to blow air through it, and with power applied I should not be able to blow air through it. Mine is exactly the opposite. The car started and ran very rich after I installed the MAF but now won't start again.

RE: Relay Location
 

stan, looks like you have addressed or looked at all of the common reasons why engine will not start. strange why it would start after dist replacement and then not and now does not seem too matter. Same after install of air flow sensor. Have you pulled the valve cover to make sure the valve timing is correct. The intake cam could jump a tooth and run bad but dist timing would still be on since it is run off of the exhaust cam. I know a reach but have seen happen and the 2.0l kind of prone to this since the tensioner is pulled back by a spring which can be overstressed during t-belt replace if not done correctly. Should be a quick check to pull valve cover and at least make sure all the basics line up. Will reread what you have looked at and done to see can see a missed step somewhere. By the way the factory manual says that you should be able to blow thru the pressure regulator solenoid with no voltage applied and not with battery applied. Make sure the passages you are testing is the one that sticks strait up out of the solenoid and the one located under the connector. The one out the other end is the vent passage and should have a filter on it. Only reason I bring this up is that have seen the filter pulled off and stuck on the wrong end which would give you the results you got. Let me know what you find out...

RE: Relay Location
 

Stan, The numbers you posted for compression seem to be indicating serious engine problem. 3-190's and a 120?