before i get started i just want to say i have searched for two days on this forum and others with no luck on finding a specific answer for my problem. ok so here it goes. i have a 2000 excursion 7.3 with a magnaflow exhaust and a open element filter. i had the clamp mod done but removed it because i was only getting 8-10mpg not towing and 5mpg towing a 6000lb trailer. now my mileage is up to about 15-16mpg not towing but i have a problem with my wastegate opening too early. every time my truck shifts(auto) my wastegate sounds like a blowoff valve. it does this even if my boost gauge is only showing 2lbs of boost. it also has a pretty good amount of turbo lag (3 1/2 inch downpipe still) and stuggles to get 15lb of boost. it also has no boost in overdrive and my wastegate is stuck open(whoosh sound). if i floor it it blows off after the truck shifts and while the rpm's are still climbing in the next gear. another thing is my boost gauge shows 1-2lbs of vacuum at idle. maybe thats just a defective gauge but it never did that before. i'm going ro disconnect the ebpv wires like i read in another post and see if thats sticking and try adjusting the actuator rod because maybe my spring in my wastegate is getting weak. it was showing 15-20lbs almost all the time with the clamp mod. do you guys have any other suggestions?

 

I'm not exactly up on the clamp mod so I'm not exactly sure what it does. But I'm willing to bet that it probably increases fuel pressure or something to that effect. If so, with increased fuel pressure you're going to get more boost. If you think it's your wastegate, try unhooking the red wire going out of your wastegate and plugging the red wire on the thread of a screw. This will keep your wastegate from performing regularly because it won't sense the extra boost and open as it normally would. Your wastegate will still open on it's own once you reach higher levels of boost. If it is your wastegate, then this should be able to tell you that I think. As far as I know, there is almost no psi at idle. My truck shows no boost what so ever.

P.S. Welcome to the forum!

 

ok, first off what you are hearing is probably turbo surge it is much more noticable when you do some mods to you truck (air intake exhaust etc.). it is not good for the turbo charger and can be corrected with either an "ats turbo housing" or a "wicked wheel" second, you may be losing boost, the common places for this to happen are around the intercooler tube boots. try tightning all the clamps on the IC boots. there are 4 of them (8 clamps) on the IC tubes and there are 2 more (4 clamps ) on the intake tubes(under the turbo charger) third, here is where it gets a little technical, if you put more air into a diesel engine and do not put more fuel into it(ie a chip etc.) you will not see much, if any HP (or boost) gain, in fact you will probably lose some low end power. unlike a gas engine a diesel does not use more air to make more power(as more air flows through a gas engine it will pull more fuel with it and make more power) a diesel is unthrottled, so to make more power or accelerate it adds more fuel, if you increase the air flow over the stock fuel delivery capacity you are not going to make much, if any more power, you will just have lower EGT's. fourth, if you want to unhook the waste gate just unplug the red line going into the gold canister on the back of the turbo charger and plug it (it must be plugged) onto one of the IC boot clamp bolts. if you want to take the wastegate one step further i can post a link on how to tighten down the spring in the wastegate actuator.

 

thanks.i fogot to mention that i have that red line disconnected. sorry. i've been reading this forum for a while and that was one of the first things i did. back then it was a definate improvement. the clamp mod is similar to the 10k mod but it's a series of diodes and a 1kresistor.

wlihntr i actually have your post saved on my computer and am going to try to adjust the actuator today.can that spring inside the wastegate get weak? i would add fuel via a chip or tuner but after the clamp mod i'm afraid my fuel mileage will drop again. why does adding an exhaust and a filter cause compressor surge? i thought adding these two items would make the turbo work easier by getting rid of the restrictions. isn't compressor surge when your trying to push too much air at too low of an rpm. it' blowing off at 2 lbs of boost.
by the way thanks for helping me out guys

 

can you move the W/G actuator by hand? IF it is really opening that easily, you should not have a problem moving it by hand. In that case, you could temporarily fix it by wiring it closed

 

If you're running a setting such as a 60hp or 80hp, you're going to enhance your truck's performance. When I set my truck to run on the 60hp(tow/haul) setting, the MPG's increased and the differnce was night and day. Depending on how you drive, you can either see +'s or -'s.

 

i'm not sure i haven't actually tried that. that will be the first thing i try tonight. will wiring it shut hurt anything? what do you use to wire it shut?

i'll have to check into that as soon as i fix my problem.

 

i would image it could but i have not heard of that being a common problem
if you get a mild chip and can keep your foot out of it you would most likley gain an mpg or 2, or at least stay the same

it does not cause it, it just amplifies it, a stock engine will do it a little. in basic terms the surge is when the turbo compressor wheel over runs its capacity to move air
you may also want to bouble check the boost gauge connections and make sure it is not leaking

 

good idea. i'll check that as well tonight and let you know what i come up with. i use clamps and zip ties on all the vacuum hoses but there is always a possibility of something like that happening. before i secured them they would blow off at 20-22lbs of boost. how long does it take to shorten the actuator rod. if i get off work early i may be able to get that done tonight. or maybe i'll wire it shut depending on how much time i have. i'd like to try as many things today as possible this way if i have a question tommorow it will still be fresh in your minds.

 

maybe an hour or two, the tuff part is its all hard to get to. cookie88 told me on some of the trucks he has done he did not have to remove the wastegate actuator to shorten the rod he just screwed it in, mine would not budge, i had to take it off to shorten it. you may want to stop by a hardware store and pick up an extra "E" clip (i think its a 1/4" but get a couple different sizes to make sure) because as stated in the instructions you will probably lose it. cookie88 also said he has run his with no clip and did not have any problems...your choice

 

thnx. i'll let you guys know what happened tommorow. again thanks a lot i knew that i would get knowledgable responses from this board.

 

ok. i checked the boost gauge connections and those were fine. i cleaned the oil residue off all the inlet pipe hoses including the intercooler and tightened them up a bit. i didn't get to the actuator because i didn't have enough light left to get to it. i'm assuming that i'll have to disconnect it to try and move it by hand so i'll shorten it at the same time. i started to get frustrated so i took a step back and tried to remember when all this started which is when i changed to the open element filter. well i remembered someone posting that the ebpv is controlled by a couple of sensors. one being the iat which i believe was in the airbox. correct?? i cut the rubber portion of the filter and stuck the iat back in but my point is that now that it's colder out the symptoms are much greater than before. i'm thinking that the ebpv is partially closed all the time. what can i do to check this?

 

you can unplug it and it should just stay open, unless it stuck. you can take the actuator arm off and see if it moves freely, its kind of like the butterfly on a carberator

 

i'll try that before i leave work.

 

after trying just about everything with no results and rereading this post i did a search on the wicked wheel. sounds like a winner from what i've read so thats next! thanks for your help guys