RESOLVED!: No joy....more 6.2L ECM questions (Newport Dave, Don S)

[jwaymer]

Ok, this is in regards to my previous post: <br />6.2L Mercruiser Alarms<br />I believe I have the cooling problem solved. I took it for a test run today after changing the riser gaskets. The manifolds and risers are "cool" to the touch and not steaming.<br /><br />I still, however, have the alarm. It is an active alarm because the intermittent beep occurs every minute. <br /><br />I have Rinda Diacom diagnostic software coming, but it won't be here until Wednesday. I also have a Mercruiser shop manual coming (I don't know when that will arrive).<br /><br />Question 1: Does anyone have a link to an online shop manual? Don S, you have posted a link to "boatfix.com" manuals, but I can't seem to find anyting out there on 6.2L's (they have a manual on big-blocks, but nothing on small-blocks). Is there one? I am trying to trouble shoot all of my sensors (mainly knock sensor), but they are not exactly the same as the BB setup.<br /><br />Question 2 (maybe to Newport Dave or anyone who knows EFI systems well ): Once I get my diagnostic software, I plan on re-setting the active alarms, going for a test ride and seeing what comes on (hopefully nothing). Is this wise? Is there anything I should do first? This seems like a knock sensor problem now. If I had a knock sensor alarm in the past, will it reset itself or does it need to be reset with a scantool, and can I assume my trouble will go away if it were reset (assuming the condition is no longer present)?<br /><br />Any advice would be greatly appreciated. I have friends coming in town for the 4th, and they think they are going boating this weekend. I am desperate now. <br /><br />Thanks,<br />Jason

 

[newport dave]

Re: RESOLVED!: No joy....more 6.2L ECM questions (Newport Dave, Don S)

Jason,<br />Good work on getting the Diacom software. I have been using it for four years and recommend it highly. Be sure to retrieve and save the Fault History before you clear it. <br /> <br />If the alarm is sounding (every minute) as soon as you start the engine, then you will not need a test ride. You will not be able to "reset" the fault code causing the alarm. You cannot reset or clear an Active Fault code. <br /><br />There will be a list of Active Fault codes and you only need to identify the one causing the alarm (some Active Fault codes will not trigger an alarm). Once you know which one is causing the alarm, you can begin making the repair.<br /><br />If you can post some of the data from the Diacom software when you get it, I can help you figure what needs to be done.<br /><br />Dave

 

[jwaymer]

Re: RESOLVED!: No joy....more 6.2L ECM questions (Newport Dave, Don S)

Thanks Dave, I'll post data when I get the software. What data would be useful to you? <br /><br />Oh, yeah, and how do you post a picture directly in the post? I tried doing so with my ex-mani pics, but they turned up broken and I had to post a link (it was probably Yahoo's fault).<br /><br />.....I'm going to drop my 289 from my '67 Mustang in if this doesn't work....j/k..learned alot about this boat so far.

 

[jwaymer]

Re: RESOLVED!: No joy....more 6.2L ECM questions (Newport Dave, Don S)

Ok, I called Rinda and had them overnight the software. It's awsome. <br /><br />Anyway, here is some data. I also did this: 1) turned on the ignition 2) the alarm sounded and beeped every minute (as usual - engine NOT running) 3) realized I had the temp sensor unplugged (from the other night while checking Ohms on it) 4) plugged it back in. 5) ECT TMP CKT HI went inactive (beeping stopped) 6) Unplugged it again (beeping started again - repeated several times). This data is from before I realized it was not plugged in. It was plugged in in the past while running, but could this be a "soft set coupler" (as we call it in the auto industry) problem? Typically, since I have had this problem, the beeping begins as soon as I turn the ignition on. It doesn't beep now. Have i found the problem? I am taking it for a water run tomorrow (with computer attached of course)<br /><br />Available power now reads 100%! I think this is a good sign.<br /><br />Let me know what you think the data is telling you. I have more freeze frame data, but it was too much to paste in here.<br /><br /><br /> System Type: MerCruiser PCM555<br /><br />2. PERFORMANCE DATA<br /><br /> Parameter Description Value Unit<br /><br /> Available Power 90 %<br /> Baro Pressure 14.33 PSI<br /> Battery Voltage 11.87 VDC<br /> Coolant Temperature 32.00 °F<br /> Engine Speed 0 RPM<br /> Fuel Flow Rate 0.00 GPH<br /> Fuel Level 1023 #<br /> IAC Duty Cycle 0.00 %<br /> Lake/Sea Temp 430.00 °F<br /> Manifold Absolute Pressure 14.33 PSI<br /> Manifold Air Temperature 79.00 °F<br /> Oil Pressure 1.09 PSI<br /> Paddle Wheel 0 Hz<br /> Pitot ADC 0 #<br /> Port Exhst Cool Temp 32.00 °F<br /> Sea Pump Pressure 0.00 PSI<br /> Sensor Power 5.02 VDC<br /> Spark Advance 0.00 DEG<br /> Starb Exhst Cool Temp 32.00 °F<br /> Throttle Position 0.00 %<br /> Throttle Sensor Voltage 0.64 VDC<br /> Trim Position 1023 #<br /> Trim Volts 5.10 VDC<br /><br />3. TROUBLE CODE STATUS<br /><br /> Current ECM Codes<br /><br /> Sensor Fault, click Read Fault button for details<br /> Limiter Fault, click Read Fault button for details<br /> <br /> Trouble Code List:<br /> PITOT CKT LO Code is active<br /> FUEL LVL CKT HI Code is active<br /> STEER CKT LO Code is active<br /> ECT TMP CKT HI Code is active<br /> TRIM CKT HI Code is active

 

[newport dave]

Re: RESOLVED!: No joy....more 6.2L ECM questions (Newport Dave, Don S)

I think you found it. If the available power is now at 100% and no alarm, it's time for a test run. <br /><br />If you can, keep the computer connected and record some data. If you don't leave the computer connected and you have a problem (alarm) again, even if it goes away, connect the computer before you shut the engine down. That way you have the alarm causing code(s) still showing as inactive fault codes.<br /><br />I don't know what "soft set coupler" is. <br /><br />Dave

 

[Don S]

Re: RESOLVED!: No joy....more 6.2L ECM questions (Newport Dave, Don S)

I'm with Dave, time to fire it up. Even if you don't take it for a run, the performance data doesn't give you much without the engine running.<br /><br />I was guessing that the "soft set coupler" meant the connection wasn't any good. It's always a good idea to do a wiggle test and even disconnect and look at each connector. I just had a Volvo diesel with an intermittent problem of the compressor not staying kicked in long enough, found a small amount of corrosion on one of the connectors that controlled the compressor, I "KNEW" there was no way that could cause the problem, but they have sense put on about 75 hours on the engine within a week and no problems.

 

[jwaymer]

Re: RESOLVED!: No joy....more 6.2L ECM questions (Newport Dave, Don S)

OK...I think I found it. The IAC alarm is active while the engine is running. This is the one that is limiting power to 90%. Sorry I don't have the data, my laptop battery died. Looking for a new valve right now. Hopefully find one locally so I can try today.<br /><br />Oh yeah... a soft set coupler is a no good connection - appears good, but isnt fully seated.

 

[jwaymer]

Re: RESOLVED!: No joy....more 6.2L ECM questions (Newport Dave, Don S)

Update: The IAC is definetly the problem. I unplugged it from the harness and the alarm goes away. I took it on a test run and everything is at 100%. The idle performance is still crappy. I previously did not have anything to compare with, but the tach showed 600 RPM (but still seemed crappy). With the new software I got, I did a tach test. The tach test showed that at 600 rpm, the tach actually reads 900. So basically, what appeared to be normal idling was at 400 rpm idle.<br /><br /> The question I have now is can I run without the IAC plugged in for a few days until the new one arrives. My understanding of an IAC is that it is basically the "butterfly" for idle speeds since the throttle plate is fully closed. But does the motor need any other info from it to perform correctly? It didn't seem like it does.<br /><br />Lessons learned from this problem (I hope other shadetree mechanics can learn from this):<br /><br />1)EFI motors need a diagnostic computer or very good trouble shooting skills to solve problems.<br /><br />2) Write ALL symptoms occuring:<br /> - my problem started as an engine alarm, led to an impellor issue,led a possible waterflow issue,led to maybe the wrong application of an outdrive type, led to an exhaust riser issue, and then to an "un related" idling issue. I was aware of the idling issue, but just blew it off as normal.<br /><br />3) When choosing a mechanic to do diagnostic work, pick one near a lake or at least one that is going to hook it up to the muffs.<br /> - See #2 above: I was lead to believe it was an overheating issue due to a faulty diagnosis. His diagnosis appearantly did not involve running the engine. I had the same results in the garage as he did, but once in the water with the engine running the true problem came out.<br /><br />4) Don't trouble shoot by replacing parts. <br /> -Find the bad part and replace it. I spent about $300 on parts so far (including the IAC). Some needed replaced anyway, but it was a desparate attempt to fix an unkown problem. It would have been nice to have had that extra money go towards a wake tower or some other accessory for the boat.<br /><br />I appreciate all the help I have received on this site, and I will definetly be on here for a while (it's kinda addictive). I just hope I don't have to post anymore problems.<br /><br />Later,<br />Jason

 

[NateCCIE]

Re: RESOLVED!: No joy....more 6.2L ECM questions (Newport Dave, Don S)

Jason, <br /><br />How much did you spend on the Diacom software/where did you get it?<br /><br />-Nate

 

[jwaymer]

Re: RESOLVED!: No joy....more 6.2L ECM questions (Newport Dave, Don S)

I called Rinda directly. It was $579.00<br /> Rinda <br /><br />I paid $108.00 for for a diagnostic scan that didn't tell me the problem. I figure now I can scan it anytime I want to and it will pay for itself pretty quickly. <br /><br />My problem probably would have been about $400 for it to be fixed correctly at a shop. $100 scan + $100 troubleshoot + $100 part + $100 labor to remove/install, doing it yourself....priceless.

 

[newport dave]

Re: RESOLVED!: No joy....more 6.2L ECM questions (Newport Dave, Don S)

Jason,<br />Good going. You stuck with it, got the right tools and sucessfully diagnosed the problem(s) . And you are right, what you have learned is priceless. <br /><br />You can run without the IAC hooked up, but it will be harder to start, idle poorly and tend to stall when the throttle is rapidly closed. The IAC is not a sensor and does not supply the ECM with any feedback.<br /><br />Dave