Wicked Rich Idle

Don W.

Stab it and steer it
Re: Wicked Rich Idle

I have a JSM DP. There are 4 roughly 90* elbows. Off the turbo the DP goes down, then back, then down again, then back into the empty cat. My WB is in the front of the last ell.

Dropbox - Down pipe with clamp.JPG

Below the ones you can see is the last ell. That's where the WB sensor is. I remember PLX mentioning a recommended distance but I don't have it. I think it was 24" from the turbo.
 

liquidswords88

I pity da fool
Re: Wicked Rich Idle

I had the same problems with my ty. The first time it was lack of back pressure in the exhaust. Only thing I can figure is that the exhaust was moving too quickly past the o2 sensor for it to get an accurate reading. The second time was when my turbo came loose from the manifold creating a huge exhaust leak. The o2 sensor was not getting accurate information. Both times the truck was so rich that it would barely idle. My exhaust was 3 inch down pipe to cat less three inch exhaust with no muffler. I ended up having to add a three inch cat and place a 2.75 inch restrictor in the tailpipe. That was the only way I could get the cross counts where they needed to be.
 

coupecustom

Member
Re: Wicked Rich Idle

Progress...

Last week I ordered the hotwire kit from SM (thanks Tom) simply because I didn't have a weather pack relay. I was able to install the kit and test it last night.

I set the FP with the truck off first. Started the truck and now the oscillation is VERY minimal. The needle moves back and forth between 1 PSI. So, between 42-43 really fast. This is significantly improved from before, where I could not even set pressure as I had no idea where it was.

Taking the truck for a drive, it performed great. Ran it up to about 7 pounds of boost on a roll in and zero hiccups. I was in shock. Got home from the drive to check out BLM at idle, it was 150, and didn't move any farther up. I noticed in open loop the truck was a little lean, so the BLM closed loop doesn't bother me much. I'll tune the truck in open loop and that should settle down that BLM number.

Took the truck out for another late night drive as I was still in disbelief of how well it did earlier. Thats when the wideband issue happened. Truck started running noticeably lean, Wideband gauge stated some where in the 16.5 range, scan master stated about 14.5. You can easily tell when it happens cause the truck will misfire, and run like crap. I got to a stop light, shut off the truck, restarted and the issue didn't happen again on my way home....so it performed great.

I think I'm going to try grounding the ECU case, not sure it will help or not, but we'll see.
 

Don W.

Stab it and steer it
Re: Wicked Rich Idle

It's difficult to quantify such things but when I tied all my grounds together it did seem to help. Read the second paragraph on page 9 of Eric's instructions on how to adjust the chip for correct operation at WOT. That's assuming you're using pram 7 to control WOT fuel. Getting things close to -0-, or 128 depending, will make a difference.
 

coupecustom

Member
Re: Wicked Rich Idle

I went ahead and ran a permanent ground wire for the ECM case today. For about a week now I've just had some alligator clips on the case to a ground bolt. The issue did occur once, however the alligator clip may have gotten bumped before that. Hard to say, but I did drive the truck nearly every day last week and the issue only occurred that one time. With the case wired to ground permanently now, I hope not to experience the wideband to ECU AFR difference again.

Truck has been running well. I used the on chip settings to adjust idle fuel to a little bit richer (three clicks). This brought down the BLM's while in park warmed up. BLM is now around 137 in park. I did notice that while in drive and just letting the truck idle foot off the gas, the BLM's were like 119, so taking fuel out. I'm thinking the happy medium of the setting on the chip is pretty decent. It still needs a lot more driving time to really let things settle in. Also, its possible I may still have a pump issue, some more driving and logging to see.

IAC maybe hair high now too, now that the hotwire for the fuel pump is done. After driving around and tossing it back into park IAC is about 38, so I need to get that down a little.

This next week I'm going to work on setting up the boost controller. Been doing great on just the wastegate, so time to see how we do with more than 7psi. goal is to turn up to 10 pounds and log it.

Amazing how much time and testing is involved just to get idle right.
 

WyoSyclone

Active member
Re: Wicked Rich Idle

I've been working a similar issue with another Innovative wideband user. I don't have an Innovative WB in front of me, but this is what worked on this other truck....

Innovative has 'Analog 1' and 'Analog 2' outputs... normally #1 is used to emulate a NB signal and #2 is used for wideband. The output voltage on these leads is adjustable and can be set via the Innovative programmer.

Innovative, along with multiple posts, say to always take the reading on the Innovative gauge as gospel. So, on this other truck we had a large discrepancy between afr's on the wideband gauge, and in TunerPro. The reason is that the output voltages on the wire used for inputting WB into the ECM had not been calibrated to match with TunerPro. If they don't match, and you are using TP afr's to tune with, you're tuning to an invalid AFR. If you're running open loop you'd be possibly dangerously off on your afr's. If you're running closed loop you'd also be in trouble because it's adding or subtracting fuel to an incorrect setting.

On this truck we programmed the WB output wire of the Innovative brain to use values of 0v = 7.35afr, and 5v = 22.39afr (this is the Innovative factory default, but they can easily get changed). This resulted in the AFR's being within .2 of each other - gauge to TunerPro.

Hope this helps.
 
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coupecustom

Member
Re: Wicked Rich Idle

Innovative has 'Analog 1' and 'Analog 2' outputs... normally #1 is used to emulate a NB signal and #2 is used for wideband. The output voltage on these leads is adjustable and can be set via the Innovative programmer.

Unfortunately, the Innovative WB/Boost Controller I'm working with only has 1 Analog out. It is the Voltage range you mentioned above; 0-5 and AFR 7.35 - 22.39 respectfully. Luckily this issue has not been a problem as of late. I did a good ground on the case to the body. I'm not positive that that was the problem, but the frequency of the issue has decreased and actually not at all lately.

The change I made to increase the idle fueling on the chip helps in some respects but not others. Right now the truck runs quite rich (to my nose) still, and I'm unable to get IAC any lower than 50 in park (when completely warm). I'm going to drop down the computer again and move the idle fuel down some. I need to get the laptop out again and see whats up. I'm thinking I'll log with it in open loop, do my very best to get IAC right and AFR right in idle with the on chip idle setting.

Something keeps telling me I have a fuel pump issue. The hotwire did help with the pressure, at least initially. It seems that after driving it around a bit though, that I end up having idle issues, meaning, when the engine is hot. I don't have the type of fuel pressure gauge I can leave connected and drive, so I'm unable to really see what's going on with it after the engine is really warm. Also noticing that more of the issues with idle occur when the tank is at 1/4 fill or lower. I'm thinking the pump is running hot. When this is occurring the computer attempts to add in fuel, but the pressure is lower, this results in less atomized fuel (raw gas), causing the smell.

I was going to start increasing boost, but given I can't really get idle right, I think thats a bad idea....so idle is still where I'll focus.
 

Don W.

Stab it and steer it
Re: Wicked Rich Idle

No lower than 50 on the IAC counts? Even with the idle stop screw screwed in. "In," turning to the right, increases the opening of the throttle butterfly's which should -lower- IAC counts.

What is your idle speed? What is your FP when at 1/4 tank with engine hot? Don't forget that any kind of application of full throttle or close to it at this fuel level is probably going to uncover your fuel pump causing a momentary complete loss of fuel pressure with all kinds of unfriendly reactions from the engine..
 

coupecustom

Member
Re: Wicked Rich Idle

right, no lower than 50. I turn the idle stop screw in to a certain point and the engine starts hunting. Moving the idle speed between 1x and 825 RPM. Backing off the screw will drop the idle to its normal 850, but again IAC won't drop. Seems like its simply to rich that IAC "has" to stay that open to keep it running. Oddly enough WB shows good, right around 14.6 or so.

To get FP with the engine that warm I really need to drive it, put it through some cycles, but my FP test gauge says not to drive with it on. So I haven't.
Don't forget that any kind of application of full throttle or close to it at this fuel level is probably going to uncover your fuel pump causing a momentary complete loss of fuel pressure with all kinds of unfriendly reactions from the engine..
That's what I'm afraid of. I have set param #7 to 10.8. When I "do" put my foot all the way down, I noticed WB only ever reached about 12.2 at best. Granted that was only 7psi (WG), but still I would expect it to be far more rich, given WOT.
 

Don W.

Stab it and steer it
Re: Wicked Rich Idle

Per the manual the IAC will "reset" (if commanded by the ECM) above 30mph. Another thing is TPS voltage it should be less than 1.25v with throttle closed. Otherwise the ECM cannot control idle.

Another check which I may have mentioned is after key on the FB runs for 2 secs. After that your fuel pressure should hold, and for quite awhile. Do you still have your EGR valve? It might be you need a new IAC. Something is sure fishy with your IAC counts. You might want to remove the TB and make sure the butterfly's are closing completely with screw backed out to check and that the shaft isn't worn. Remove the IAC cover/mount and make sure the gasket is not damaged and the passages are clean. I just find it strange that you can't control the IAC count with the throttle stop screw.
 

liquidswords88

I pity da fool
Re: Wicked Rich Idle

The iac passage can be accessed by removing a cover like plate from the throttle body. The holes are small and do get clogged up with carbon and what not. If you want to try a different iac , grab one from a throttle body chevy truck. V6 or v8. Those trucks seem to be all over the place, and it is a direct swap.
 

coupecustom

Member
Re: Wicked Rich Idle

Another check which I may have mentioned is after key on the FB runs for 2 secs. After that your fuel pressure should hold, and for quite awhile.
When I did have the FP gauge on the FP does hold very well...hardly any pressure drop after several mins.

Do you still have your EGR valve?
I do not have an EGR. Block off plate from SM

It might be you need a new IAC. Something is sure fishy with your IAC counts. You might want to remove the TB and make sure the butterfly's are closing completely with screw backed out to check and that the shaft isn't worn. Remove the IAC cover/mount and make sure the gasket is not damaged and the passages are clean. I just find it strange that you can't control the IAC count with the throttle stop screw.
I had the Throttle body off a couple of months ago and was able to clean out all the passages really well. The blades do close nicely.
I should note, the IAC numbers do go down a little bit with idle screw adjustment. Its just that I run into the idle hunting issue when they are lower than 50. I recall that with the TT chip's idle setting 0 instead of 3+, the IAC's were at ~30. I had moved the idle fuel setting in my attempts to get the truck running open loop and a slightly rich AFR (14.3). When I made this adjustment, truck was above 160 degrees (thermostat level), maybe that's simply not warm enough.

Since these numbers move around and it goes from these rich to lean with raw gas conditions, this is why I keep coming back to a possible pump issue. The truck is terribly inconsistent, which makes it hella frustrating.
 

coupecustom

Member
Re: Wicked Rich Idle

Last weekend I had enough and pulled the gas tank down. That is one tough job :tdown: As I was disconnecting the fuel lines the sending unit metal lines twisted and tore a little. Now I will have to get a new sending unit. Its aged enough that I think I would have replaced it anyway. Wiring actually looked in good shape on the outside. No insulation melted or anything like that. I was half expecting that, but pleasantly surprised.

I'll wait to open up the tank till after I have the funds to pay for a new pump and sending unit. I know I will eventually run E-85 so I'll be installing a Walbro 450.
 
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