I have acura cl auto. It cranks but doesn't start. I read around and already changed the main relay under the dash. Still doesn't start. I looked at all the fuses. None is blown.

Funny thing is this all started happening after I changed all the coils & plugs as part of routine maintenance at 200k. The car was running fine. It still ran fine after I changed the coils & plugs but a few days later, it started giving me starting problems. Now, it just cranks but doesn't start at all and just sitting on my driveway.

Battery is okay. I'm pretty sure I hear the fuel pump prime when I turn on the ignition. After trying to start many times, the exhaust pipe smells of gasoline, so I think I'm getting fuel. I should be getting spark since I'm reading 12v at ignition coil fuse under the steering wheel. and coils are all brand new (I switched back to OEM just to make sure, but no change). The new plugs are the denso iridium #3396.

Any suggestions? Thanks all.

 

Changing coils isn't part of routine maintenance, and you should check to verify spark with a spark tester.

 

you may have also flooded the engine with too much fuel

 

thanks for replies guys. yea I pulled main relay, cranked it for about 20seconds, no change. wouldn't start. engine crank sounds like it has compression. so i don't think it's horribly flooded yet.

my suspicion was also spark, possibly one of those cam/crank sensors. I just bought autel autolink al519, and it's not giving me any codes. looks like the ecu is reading rpm during crank so I figured it should at least try to fire. I don't have the spark tester... I can however try to rule out every potential culprit for no-spark situation. i already did new coil, plugs, checked fuse, relay, is there anything else for the spark? and is there an easy way to check for fuel pressure on this engine?

 

Get a spark tester. They're not expensive.

 

I am already troubleshooting under assumption there is no spark. What is there to check for no-spark no-start situation? I already replaced the main relay, checked ign coil fuse, new coils/plugs. my Autel is reading rpm, so I assume ECU is getting power. is there anything else?

 

You seem to be dead set on making assumptions and continuing to guess instead of diagnosing the problem. Good luck with the repair.

 

Did you replace it with a brand new main relay, or a used one from the junkyard? If used, it could be just another bad one. Seems to be a common occurrence on these cars where the main fix is just reflowing the solder. I've had to do that on my car, and my girl's.

An unconventional spark test you could do that I don't recommend (I'm not responsible if you mess anything up), even though I have done it, is pulling one spark plug at a time keeping it in the coil pack, putting the tip to the engine to ground it (somewhere metal), have you or some one crank it, and then have the other observe to see if there is a visible spark.

 

i got a brand new one from autozone.

 

yea i can try that. i just did the plugs so i got the old ones laying around. my point was.. i think i addressed every component responsible for spark-relay,fuse,ecu,coil,plugs. so even if it's the spark, i'm not sure what else to check.

 

looked at the timing belt and it looks partially shredded. it looks tight and i don't think it skipped but i guess i never know. need to check compression.. do the valves hit pistons on these engines?

 

Well finding out if it is the spark needs to be ruled out first.
If you have a multimeter, it might be worth checking out the pins of the main relay to see if it's actually get power. My money is still on it.

 

i got 12v at the harness.

 

Doesn't mean it's giving the signal for the plug to cause a spark, only that the harness is getting power.

 

yes i get that. I don't think I'm getting spark, so I replaced main relay, checked fuse, ecu (my OBD reader does register crank rpm? not sure whether this is good enough check) ,coil (tried both new delphi unit & old oem), and plugs (new). is there anything else I should be checking for?

 

or if there's a way to figure out if ECU ignition drivers are fried... that'd be helpful as well.. thanks in advance.

 

You could spend the money on a replacement ECU, but you'd be looking at spending about $100 on a unit, then another $100 on having it reprogrammed, unless you go another route that involves a CEL that will never go away.
I've got like 4 ECUs sitting in storage for this very reason. But testing individual parts on the ECU isn't likely unless you're an electronics expert.
I would say check and see if there's a wire from the ignition/coil packs to the ECU and test and see if that works, but you already checked harness power, and checking the signal would still require cranking.

Something is amiss here. Check the main relay pins with a multimeter, recheck fuses, check the wires in the entire harness from the coil packs to where they enter into the cabin for any shorts, check the intake for a dead rat choking the intake.

 

I think it's possible the new delphi coils I have put on may have lower resistance than stock and fried my ECU ignition drivers... I mean it's a far shot but I can't think of much else. I can check continuity of coil signal wires. those haven't been touched but i can check.

I don't mind constant CEL. can I just buy the ECU on ebay for like $20 and plug it in? or does it need to be programmed to my specific vin to send signals to injectors & coils?

and does dash need to come out to replace the ecu? if so, i may honestly just junk this car... sucks b/c i just spent like $500 in parts that I put on..

 

here is my ghetto spark tester

 

Don't know why coil packs made for this car would cause a problem with the ECU.

I'd recommend getting the ECU reprogrammed, as the method I'm mentioning is against the rules to post how-to I think.

You can remove the ECU without removing the dash. You just need to pull the carpet out from the corner of each side of the console, and it's sitting there, held on by two bolts. Pretty easy once you figure it out.

What's the say on the spark tester?

 

i couldn't really see the spark too well. never done this before so not sure if it's normal to not to see it through windshield b/c the sun is pretty bright out. I was going to try again at dusk. i just put the plug on my new coil & grounded the body of the plug to the battery ground.

good news on the ecu removal. this car got me thru alot so i want to save it if i can.

 

It'll just look like a small electrical arc for half a second each time it's cycle repeats. Easier to see in the dark, but visible in the light as well.

Well if you choose to junk it, I could use a new passenger seat computer and actuator. I'd prefer to not see another junked CL though.

 

i couldn't really see any spark. i think the only variable left is the ecu. i may just buy $20 ecu on ebay and plug it in... if that doesn't work, you can have whatever you want as long as it won't be too involved for disassembly. just pay the shipping. thanks for your help

 

do we have fuel injector fuse somewhere? I can't find it on any fuel diagrams

 

Acura TL 2000 start and run for a few mile and stops. Wait several minutes and start again. Scanner said that the ECU is malfunctioning. Can I use an Acura tl 2003 scanner? Please advise. Thanks.

 

I meant Acura 2003 ECU not scanner.