Surging during warmup...

[a_housos]

Hello guys,
Well every couple of months I try to get this project going. Let me give you some info on the car. I'm running E85 on a Ford 347 with coil on plug, 8 160 lb injectors, and an intercooled turbo. The fuel system is an Aeromotive Pro pump with -10 lines to and from the tank. An Aeromotive regulator set to 43.5 psi.

During warm up it gives me problems. Oddly when I first start it the motor starts fine and settles into an idle at 80* (normal starting temperature here in AZ). Once it gets to about 100* it starts surging. Almost like someone has flipped a switch. This seems to get worse and worse until it reaches about 160* when it abruptly starts idling smoother. Once it reaches 180* it goes back to idling nicely with just a touch of the surge. I've tried attaching a data log of this whole episode from this morning, but it says it is too big. Any suggestions on getting past that? It is about 5 megs in size. Can I somehow break that into several files??? Or is there another way to host the file?

I have noticed that there were 3 sync errors in that time. The first one was probably when it was cranking before it started. The other two happened sometime during the warm up. I don't know if that has anything to do with it, but I thought that I would throw it out there.
Thanks!
Tony

[kb1982]

What kind of throttle body are you running. Wondering what kind of IAC setup it has on it. BTW, anyone that wants to share files that are relatively large, you can create a gmail acct (google email, or just login to yours if you have it) then proceed to google drive. There, you can upload relatively large files. Make sure the file is set to public, then you can simply copy the link to the file that you want others to see. Here is an exampl. https://drive.google.com/file/d/0B2xLL_ ... sp=sharing That is the base tune for a 1995 Mustang using a MSpnp for example.

[a_housos]

My throttle body is the same as this one from DIYAutotune...

http://www.diyautotune.com/catalog/four ... p-512.html

It is the 4bbl style with a stepper IAC. Although it is from a different manufacturer, it is the same throttle body.

I am going to try to set up the google drive. I will let you know when I have that complete (or when I totally screw that up!).

[a_housos]

Ok, I tried setting up the Google drive, but my computer is too old to work correctly with it. So here is what I was able to do. I cut the files up into 1500 record lengths in Megalog viewer. Then I saved them as a different name. It will only allow me to download 3 of them at a time. So let me see if I can split this into two posts.

[a_housos]

Here are the final three...

Please view them all in line per the numbers.

[slow_hemi6]

What is the go with your battery voltage is it really that low?
What is the go with the big block of 30 degree spark timing at low rpm? Lighting off the E85 I take it? Every time the engine bogs down and map goes over 60kpa your spark map pulls a bunch of timing out and by 70kpa you have ripped out 15 degrees. That's the exact opposite behavior of what you want. Normally on an idle dip, you want to crank a couple of degrees extra in to stabilize.

[kb1982]

Click the link that I shared earlier and take a look at the timing table. I believe you have way too much timing at idle. As stated earlier, you want the rpm bin that is lower than your idle rpm to have a higher ign timing. The increase in timing when your rpm drops, will surge the motor higher in rpms, and keep it from stalling out and shutting off. I will state that im not an expert on tuning, as Ive only tuned my car which is a ford 347 also with a v2 supercharger that uses a ford style pwm iac running 93 octane. I have no relevant experience tuning for e85, besides what Ive read, but Im gonna take your msq and adjust the timing to what i think it should be in the idle range. By no means, should this tune be used for anything other than trying to get a stable idle. Also you need to correct the battery voltage also as previously stated.

[a_housos]

I wasn't even thinking timing to be honest with you. The two things that jumped out at me were the loss of sync at the point where things get crazy and the loss of sync when it goes back to operating normally. I didn't know if that was a cause or effect of the craziness. Part of the weird timing is that I've gotten some advice that said that you need a ton of timing for E85. I've also had problems getting the rpm to be high enough at idle and playing with the timing seemed to help. At one point I was just thinking that maybe I should have changed the timing to mimic a locked out distributor to eliminate a variable. So for those reasons you are seeing some really strange stuff in the timing table as I tried to correct these issues. Anyhow, I am going to try the one you sent to see if that clears up the idle issue kb1982.

The other thing that jumped out at me was the WUE. That is way nuts the way it is set up. And that came from running the WUE a few times in Autotune.

I noticed the battery voltage part as well. I think what it is reading is accurate. I may need to speed up my alternator by changing the pulley. I had originally slowed it down to keep it from over speeding, but maybe my calculations were off. I will revisit that as well. But first the timing to see if that corrects the surging.

[a_housos]

Ok, here are the results. Changing the timing really didn't make a difference at all (see the msq attached). I did change the WUE just a touch around the 60.0* and 80.0* areas. I still have problems around 112* where it started surging like mad. This time there were no sync errors at that point. (See modified 1 log at 6688.24s)

It kept surging until it reached almost 180*. At that point (See modified 2 log at 7023.168s) I had a sync error and the idle stepper cycled from 40 to 100 then came back down to 40 at 7028.208s. The surging changed in frequency but continued. At 186* it surged one last time, the stepper cycled again and I had another sync error. Then everything smoothed out nicely.

I know that I am still having a voltage issue (I haven't done anything with my pulleys on the alternator yet). I suppose that could have something to do with it, but I wouldn't expect it to settle down above 180*. Any suggestions are welcome!

[a_housos]

Anyone? I'm getting desperate here. This car has been sitting too long.

[slow_hemi6]

The first thing I would do is get that charging system working so you can stabilize the supply voltage. When the voltage fluctuates as it is doing during the surging, the ecu will be changing the PW constantly as it tries to compensate. It's no doubt complicating things if not the whole issue. Timing still jumps around through about 6 degrees during the surging.

[a_housos]

I will try it without the alternator tonight. I'm charging the battery right now.

Could the dwell play into this? I was looking at the datalog in Megalog viewer and it seems to surge when the dwell drops to 3ms. Of course like the timing this could be the effect and not the cause. Just something going through my feeble mind.

[slow_hemi6]

You can try that but it's not really going to help as your alternator does not excite and provide any charge voltage as it is. You are just disconnecting something that's doing nothing. If you actually want to drive this car, fix it is my recommendation.

[a_housos]

I thought the reason I was getting spikes in my voltage is because the alternator was on the edge of exciting at idle rpm. When the motor rev'd I figured it was charging and when it dropped off the voltage dropped as well. My thought was to leave the charger on it with the alternator disconnected so I would have a consistent voltage throughout the test. But after reading your last post, I won't argue. I changed the pulley tonight but I am going to have to wait till morning to get the right sized belt. I didn't have one in the garage that would fit. But the battery is all charged up and ready to go once I get that. I will post the results once that is hooked back up.

[a_housos]

I've just about had it with this MS3. I went and put the smaller pulley on the alternator. Started it up today and now it was idling at 700 rpm. This makes no sense at all. The pulley has nothing to do with the idle speed. So to make sure everything was charging correctly I put my 40 amp charger on it while it was running. Exactly how I wanted to try this in the first place. Anyhow, the voltage was relatively stable between 13 and 14 volts. It reached a point in the warm up again where it started the surging. It stalled and wouldn't start back up. After a half hour of trying nothing was seemingly working. Pulled a plug and found them dry with black fluffy carbon (indication of rich mixture, but certainly not fuel fouled). I was expecting to see it flooded (wet) from trying to start. I cycled the injectors using the test program to make sure they were working and they did. So I held the throttle open and after some cranking it finally sputtered and started. Then it settled back down into the 700rpm range and started its surging again. Now it leaned out completely. This doesn't make sense at all. Half the time this thing is pig rich. I start it again and it's too lean. I rev it up and I get tons of sync errors and it backfires. I don't know where to go and nobody seems to have any ideas. I am not so vain as to think that I couldn't have screwed something up, but all I did on this was the wiring of the harness. If it was consistently doing the same thing every time I would say that it was something that I did. But it's almost as if there is something wrong with the MS3pro that I have. This is my last try. Is there anyone that has any kind of idea what this could be???

[slow_hemi6]

Hooking up chargers to a running car can cause problems because they can inject noise into the positive supply. However if you have stabilized the supply voltage then that is one problem down. You have to log it again, and post it up.
BTW if you changed the pulley and the alternator is now producing charging voltage that means the alternator is now a load on the engine and the increased voltage changes many things that the ecu has voltage compensation for. To say it should not effect the idle is incorrect.

[a_housos]

Ok, I can see it influencing the idle. But to the tune of almost 400 rpm?

Here are logs. This was the latest one after it finally started again. Almost up to temperature. I don't know how anyone will make heads or tails of this, but here you go.

[a_housos]

Note the 81 sync errors.

[slow_hemi6]

It is loosing sync a lot there. Is that with the charger connected or disconnected?

[a_housos]

Charger connected...but I have observed that it will lose sync any time I rev it above idle. You'll see from the earlier datalogs that just during an idle it has a tendency to lose sync. Keep in mind that on those first datalogs I was trying to show what it was doing on warm up I did not move the throttle at all like I had to in this last one. It did not lose sync a lot mind you (a couple of times during warm up), but it was enough to trigger the CEL. I'm using hall affect sensors (the one on the crank was purchased from DIY, the cam sensor is a stock Ford unit) for both the cam and crank sensors. I suppose it is in the realm of possibility that one of those is intermittent, or that my crank or cam wheel are a problem. I am using LS truck coils (set at 2.5ms for dwell) for a coil near plug setup. I used the shielded wires from DIY and routed them separately from the rest of the harness (except where it goes through the firewall in the bulkhead fitting). I did a composite log of the crank sensor during the 81 sync losses if that will help, but it is so large I am back to the issue of how to host a file that big.