Low rpm full boost lack o power.

[SouthCaliVR4]

OK, it's my turn to well err... turn to the group. my dog acquired a wire fetish & before I became aware of said fetish he ate both the power cords to my modis & I have not been able to find the time at work to try & trace this with their scanner as I await new cords. I have checked everything data wise static, Have a power cable that will run my scanner but not enough spare voltage to charge the effen batt, all looks correct but the issue only occurs under load /ubbthreads/images/graemlins/banghead.gif

My issue; Intermittent loss of power through entire rpm range & max boost levels well below where I should see much if any. I am running a evo3 16g set to 15 lbs boost. normally boost begins to build at 22-24 hundred & is in full by 32. when issue shows I'm getting full boost @ 2k & on up but the car wont get out of it's own way. I hit the clutch rap it out a few times & bam, she's back to running right. my first thought is ignition (new plugs & wires, plugs gapped to .27) feel like I'm loosing a cyl, maybe two, & that the unburnt fuel is precharging my turbo.

History; car had perfect drivability till I put her in storage for two years, upon getting home & firing her up, she ran like crap. I drained the tank & found a sh*t ton of water in the tank, I think I got a tank full of bad gas just prior to storing her. drained the tank, removed the fuel pump assy & sucked out the sump ran gas through the tank & again drained & sucked out the sump, disconnected the return line & flushed out the lines with a couple gal of fresh gas, changed the fuel filter, cleaned the injectors & added a bottle of heat. though much improved this intermittent issue has come up. feeling the plug wires might be compromised I swapped plugs & wires. no change. I have checked virtually every connector & the ecu, ohm tested the injectors & coil pack. cas is good.

So... who has had this issue & what fixed it, I suspect I may still have an ignition coil or ignitor problem, but seeing as how the intermittent issue duplicates the water in fuel issue I am half inclined to think injector sticking due to remaining contaminents from the whole water in the fuel thing. /ubbthreads/images/graemlins/dunno.gif

with any luck I can find a 1g in the wrecking yard this weekend & score injectors, igniter & coil pack, which I'll try one at a time but I am hoping someone knows exactly what I'm talking about & can shoot me the sure fix /ubbthreads/images/graemlins/blush.gif

thanks in advance /ubbthreads/images/graemlins/cool.gif

 

[broxma]

Try and drop the gap down to .023 or so. I have extra ignitors and a coil pack I believe. If you can't find any let me know. They are just thrown on my bench atm so not doing anything.

I also have about 50 Dodge Coils if you want to cobble a COP ignition together. You'll need a plate but other than the wiring it's a bolt on affair. I'm running a .022 gap right now at about 17 psi on a horrible tune with no real issue. I am however considering going to a dual GM Aurora coil setup instead because I started breaking up at 19 tonight.

For reference, when I got my evo and did some work to it, I cranked the boost up to about 25 psi and started running into spark issues. I decided to design my own ignition using the Aurora coils and never had any problems after that. I am using the COP on the GVR4 only because I wanted to see how high I could get the boost before blow out became a problem. My issue with the Evo and the Galant has been the same. It sounds almost as if the car is skipping a firing sequence, like it's not stuttering or sputtering, but that the motor turns over without making any power. As if the spark is not there at all or not complete.

/brox

 

[SouthCaliVR4]

Yea, for sure it's not a hard miss, just full boost & no power. it has been same same for a couple weeks, some days it runs perfect others it just keeps doing it. my commute is rather stop & go but I just got back fro a test drive & a steady state cruise definitely brings it on. I don't think it's a boost related spark blowout only due to it not being present under heavy load only. when running right I'm pulling ten to twenty inches of vac @ 2700 & 75mph then suddenly it starts feeling bogged out & any amount of throttle gives me full boost & no power. As always tag the clutch rap it up to 4k-5k a couple times & it starts running right again for a while /ubbthreads/images/graemlins/dunno.gif

typically if I want to I can drive around never hitting boost & she'll run right with traffic, my motor is 9 to 1 with a few degrees of timing pulled to avoid knock. I'm definitely getting unburnt fuel into the hot side by sound & symptom it's just a question of injector or ignition.

thanks for the offer on parts, definitely appreciate it. I do have another off topic question for you broxma, Running the evo ecu, This is new to me, what are the advantages of running this one over the stock eprom? better out of the box ignition & fuel profiles? Does this allow running evo mas & injectors without further mods, assuming I have an upgraded f/p & reg? And what year ecu are you using? there is a bunch of wrecked evo's around here & I may be interested in this.

 

[broxma]

You have to use an Evo 8 ECU because the Evo 9 has MIVEC and hasn't been made to work yet.

Why the Evo ECU? Tuning. It is by far the most flexible and easiest system in my opinion and can do anything most aftermarket EM systems can do. Speed Density, map switching, Valet, NLTS, Launch control, you name it, the guys at EvoM have figured it out.

Another thing is cost. It is my opinion that this has not been done more often because there is still a market for 1G and 2G EPROM'd boards out there. The reality is, after you pay for the chip, the socket, the cables, the Palm, etc, you have eclipsed the cost of the Evo ECU swap. Total cost, if you already have a laptop as I assume everyone does, is 150 for the ECU and 100 or less for the cable. I could probably even pin out my current cable and make one for 20 bucks. Other than some soldering and time, that's the entire outlay. You need a few harness clips which can be had off of common junkyard cars but that's about it.

In addition, every EPROM setup I have seen has some palm pilot thing mounted in the car somewhere which I hate. I like being able to plug in my 10.1 laptop, pull logs all day and go into my garage and sift through everything in .csv.

The biggest hurdle is understanding peripheries and expanded tables. The Evo ECU has many options which are not shown as variables when you initially open the map. All of the options are there and can be changed but the majority of them are concealed by default. You have to modify the base .xml files to make these variables appear and it can often be confusing. Plus, many of the variables are in hex or are hidden at some digit within the code specific to the ROM ID. Fortunately, the guys over at EvoM are pretty on the spot with getting all the info you need. Most people run just one of a few maps, for example, almost everyone with an Evo 8 runs 94170015.

Considering that a stock Evo ECU has powered a car with like 700 hp already, I'd say it has all the tuning ability needed for just about anything.

Now the Evo seats? Those are just comfy. Should have mine in a few weeks.

/brox

 

[SouthCaliVR4]

We we're slow today & I may have figured this out, I'll post back up after some drive time, probably keep it to myself if it doesn't work /ubbthreads/images/graemlins/devil.gif

 

[SouthCaliVR4]

Got her figures out & now fixed, Pulled my fuel rail & found a bunch of corrosion inside Also in the injector prefilters. tried cleaning the rail & replacing the prefilters along with another fuel injector cleaning. while that definitely changed it up a bit, problem was still there. today I scored a fuel rail & injectors off a 1g being parted out locally, again replaced the prefilters & cleaned them, problem solved!!! I suspect one or more were hanging up due to corrosion or corrosion residue & dumping an excessive amount of fuel which the ecu tried to comp for by leaning out the cyl's that it still had control over, giving me a lean misfire on those while the unburnt fuel fired off in the mani & spooled up the turbo. I'm guessing here but the no load rev up would then free up the sticking injector till the process started all over again.

On the bright side after three more or less back to back injector cleanings I doubt there is any carbon left in my combustion chambers.