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hondasteve · May 25, 2009, 10:11 AM

94 civic lx 1.5l cranks fine but no start. Did some research on internet. No sound from fuel pump or relay clicks. Replaced main relay with new one- no change. Jumped terminals 5 & 7 and fuel pump comes on and I hear one click from a relay somewhere. Checked for spark- good on all 4 cyls. With 5 & 7 jumped I get fuel to the filter but still no start. ECU fuse is good as are all fuses under dash and underhood (that I can find). ECU ground appears fine at the chassis. Check engine light comes on and stays on. Is there another relay or fuse related to the fuel delivery system that I nedd to find and check?

TxGreaseMonkey · May 25, 2009, 10:19 AM

The ECM has likely failed; therefore, perform the K-Test on the ECM:

Remove the MAP Sensor connector and turn the ignition switch to ON (not start). Using a multimeter, check for 5 volts going between the MAP Sensor connector's reference wire (+) and ground. As you look at the connector, this is the socket on the right. Really press the black test lead into a cleaned main ECM ground on the thermostat housing. If the voltage is low, it's probably indicating ECM failure. Most failed ECMs will record a fraction of a volt. To me, the K-Test is simple, elegant, and accurate.

Here's how to replace the ECM yourself:

https://www.askmehelpdesk.com/cars-t...tml#post235038

This may help you:

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 under-dash fuse/relay box; ECM (perform the K-Test); Main Relay; or the Ignition Switch. Perform tests in that order. In most cases, it's either the fuse or the ECM.

hondasteve · May 25, 2009, 10:31 AM

I'm stranded right now with no volt meter to test with. I'm trying to get a buddy to bring one over but no word on when that will be. Any other way to check the ECM? And just to save a little time where's the MAP sensor located?

hondasteve · May 25, 2009, 10:39 AM

I'm trying to get one but I'm stranded at home right now. No word on when I can get a voltmeter. Any way to check it otherwise?

TxGreaseMonkey · May 25, 2009, 10:40 AM

There's no need to open another thread, so I merged your postings.

There's no other way to test the ECM--it requires a multimeter. The MAP Sensor is located along the firewall, just behind the throttle body. Look for a hose going from the throttle body to the MAP Sensor. It doesn't get any easier than this. If the K-Test indicates the ECM is bad, it will have saved you a ton of money. Look for a remanufactured ECM, with a lifetime warranty (Cardone, O'Reilly Auto Parts). It likely costs around $275, instead of a $1,000 from Honda. Plus, the Honda ECM only comes with a 1-year warranty.

hondasteve · May 30, 2009, 11:55 AM

Don't know how to navigate this sight as far as being able to ask you directly from my profile or thread or whatever. Anyway, girlfriend was in hospital since tues. so this is my first chance to check MAP sensor voltage. I need to kinow if I'm doing it right becvause the reading on the voltmeter is 4.98. First, is my setting on meter correct: it's switched to DC and is on the number 20 on the dial. Second, I have a MAP sensory device directly mounted to the throttle body. It unclips and has three inserts. I inserted the Positive into the one on the right and connected the negative to the cleaned ECM ground. The wires running away from this sensor run over to the driver's side wheel well and has 3 different connectors there so my first instinct was to check the one on the throttle body. I don't see anything on the firewall behind the throttle body that is connected into the MAP sensor on the throttle body or anything that looks remotely electrical. Thanks for you help man- I don't know anybody personally that knows much about hondas or this type of problem.

TxGreaseMonkey · May 30, 2009, 12:14 PM

You did it correctly and your ECM is fine.

TxGreaseMonkey · May 30, 2009, 12:22 PM

Since the Check Engine Light stays on, a code is stored in the ECM. Here's how to find out what code or codes are stored:

https://www.askmehelpdesk.com/cars-t...tml#post832012

Afterwards, write down the codes and tell us what they are. The solution to your problem will come from checking for codes.

TxGreaseMonkey · May 30, 2009, 12:39 PM

Go back and retest all under hood and under dash fuses with the multimeter. Turn the ignition switch to ON (Position II) and test for power through each fuse:

https://www.askmehelpdesk.com/cars-t...tml#post252145

hondasteve · May 30, 2009, 12:50 PM

I couldn't find you're recommended test for the ecm error codes on the link you gave me. I have seen two other methods online though. The first was to check the LED on the ECM and count the number of blinks- problem is though is after looking at the ecm I can't find the led where it was said to be located or anywhere else visible while it is still in the vehicle. Correct me but the ecm is located on the passenger side ender the carpet on the sidewall. Another test suggested placing a jumper wire in the plug that has two inserts and checking the cel for blinks. So no luck on either. Going out now to check all fuses with meter- thanks and will check back in a few.

TxGreaseMonkey · May 30, 2009, 01:05 PM

You need to stop opening new threads. On this thread, just post where it says "Answer this Question." It's not that difficult.

hondasteve · May 30, 2009, 01:07 PM

OK- if I'm doing it correctly all fuses are good. I left the voltmeter on the same setting (dc, 20) and touched each side of the fuse. All fuses read 0.00. The only change was that some of them showed a negative symbol next to the 0.00. I've also manually pulled and checked every fuse in the underdash and anderhood panels and visually inspected them. Note: one of the fuses that showed the negative symbol was the one underhood for the ecu but visually it checks out fine and read 0.00. Thanks

hondasteve · May 30, 2009, 01:09 PM

Originally Posted by TxGreaseMonkey

You need to stop opening new threads. On this thread, just post where it says "Answer this Question." It's not that difficult.

10- 4 will do it this way from now on- thanks for the tip!

TxGreaseMonkey · May 30, 2009, 01:13 PM

If the ignition switch is turned to ON, the meter should read battery voltage (12+ volts) on both test points on a fuse.

hondasteve · May 30, 2009, 03:06 PM

Originally Posted by TxGreaseMonkey

If the ignition switch is turned to ON, the meter should read battery voltage (12+ volts) on both test points on a fuse.

Ok- get this. I went out to check the fuses again (the right way) and when I turned on the ignition switch I heard the relays click and the fuel pump come on! I turned it over and it started up! I did check all the fuses and they all turned out good. Guy at the parts store said I probably have a leak somewhere that got something wet and once it dried out everything was OK. I checked out the car and noticed the weatherstripping on the driver's side of the windshield is totally missing! I got some windshield sealer and sealed it all the way down. I also looked around the sill below and around the corner of the windsheild and I'm wondering if there are any spaces that might let water seep into the area below where all the relays and fuses are located? Any ideas on that? Anyway, I can't thank you enough for all the help you've given me and if I wasn't dead broke I'd support you- maybe in the future I'll be able to. I'm sure you'll hear from me again anyway. Thank you!

TxGreaseMonkey · May 30, 2009, 03:41 PM

I'm skeptical that the problem was a water leak on the driver's side. I'm wondering if you have intermittent ECM failure. If the CEL comes on and stays on again, perform the K-Test. Instead of 4.98 volts, it'll probably be .33 volts. I hope I'm wrong.. . Only time will tell.

hondasteve · May 30, 2009, 03:57 PM

Originally Posted by hondasteve

94 civic lx 1.5l cranks fine but no start. Did some research on internet. No sound from fuel pump or relay clicks. Replaced main relay with new one- no change. Jumped terminals 5 & 7 and fuel pump comes on and I hear one click from a relay somewhere. Checked for spark- good on all 4 cyls. With 5 & 7 jumped I get fuel to the filter but still no start. ECU fuse is good as are all fuses under dash and underhood (that I can find). ECU ground appears fine at the chassis. Check engine light comes on and stays on. Is there another relay or fuse related to the fuel delivery system that I nedd to find and check?

I gotcha. I have read a few posts about intermittent ecm failure. Also, I forgot to mention in my original post that we had a week of solid rain here and the car had sat two days in it before I tried to go anywhere. It does seem odd to me but like you said only time will tell. I'm out of work right now so money is extremely tight- once I have a little extra I'll pick up a cheap voltmeter to keep on hand so that I can do the K-test immediately. As of right now the cel does come on and go off as it should. Thanks again and I'll keep you posted.

TxGreaseMonkey · May 30, 2009, 04:02 PM

Your situation reminds me of my own three years ago (this month). Disconnecting the Map Sensor connector suddenly allowed the CEL to go out on my 1993 Civic DX and the car started as if nothing was wrong. Within a day or two the car would not start again. From that experience, I developed many of the tests that you see under the Sticky, including the K-Test. I ended up installing a remanufactured ECM from O'Reilly Auto Parts, with a lifetime warranty. The car has been perfect ever since.

hondasteve · May 31, 2009, 06:24 AM

Originally Posted by TxGreaseMonkey

Your situation reminds me of my own three years ago (this month). Disconnecting the Map Sensor connector suddenly allowed the CEL to go out on my 1993 Civic DX and the car started as if nothing was wrong. Within a day or two the car would not start again. From that experience, I developed many of the tests that you see under the Sticky, including the K-Test. I ended up installing a remanufactured ECM from O'Reilly Auto Parts, with a lifetime warranty. The car has been perfect ever since.

Current situation: cel stays on for approx. 10 seconds, goes out, fuel pump/ relays engage, etc. I had the feeling you were correct about it not having to do with the wet weather. Also, ignition was replaced by previous owner due to the loss of the ignition key. Ever since, the SRS light stays on all the time. The mechanic who did the work said he didn't know why. Could this possibly be an ignition switch problem? This is the very first time it has happened since I've owned the car (6 mo.s). Or is this a telltale sign of ecm failure. Thank you!

hondasteve · May 31, 2009, 06:24 AM

Originally Posted by hondasteve

Current situation: cel stays on for approx. 10 seconds, goes out, fuel pump/ relays engage, etc. I had the feeling you were correct about it not having to do with the wet weather. Also, ignition was replaced by previous owner due to the loss of the ignition key. Ever since, the SRS light stays on all the time. The mechanic who did the work said he didn't know why. Could this possibly be an ignition switch problem? This is the very first time it has happened since I've owned the car (6 mo.s). Or is this a telltale sign of ecm failure. Thank you!

PS- car does run after waiting for the cel to go out.