Must Read, How Does A Missing Link Work?
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Must Read, How Does A Missing Link Work?
Ok, I need a detailed diagram of how a missing link works. For about a few weeks ive been having this problem of my car cutting off and on" at low rpms or idle.This would be randomly below 3k rpm or at idle in VACUM. Then i came to a point were i singled out the problem. For example, ill drive 25-30mph, drop the car in 5th, at this point the rpms would be below 1500 rpms. Then i stepped on the gas, of corse the car reacted really slow and rite as the needle came to 1500 it would "cut off and on" , just a real quick flicker off and on. This told me it was a map sensor problem. Up to this point i have had no CEL, and the only time it would show is when the car would do a quick flick off and on then i would see the CEL but it would go away soon as the car came back on, wich is less than like half a second. I have tryed trouble shooting in many ways. To make a long story short i figured out what the problem was. I removed that little filter on my missing link and the car idles like ****, but it doesnt "cut off and on" randomely any more. I drove it out like normal, droped the car in 5th, rpms below 1500, and jammed on the gas, now it sputtered and acted slugish, wich is what i expected. But it didnt cut out at all. I road the rpms all the way to 5k in boost with NO PROBLEM. When cruising i would also have this problem below 3k rpm. With out that little filter in the ML the car runs shitty. So I pulled it out and im in the process of cleaning it with soap and water. My question is does any one have a detailed diagram of how this missing link works? I want to better under stand how it works. I know it just "hides boost from the MAP", but i like knowing exactly how thinks work so i can diagnose problems when they come about. I hope this helps you turbo guys out. I was about to take this dam thing to the dealer ship and have them look for a electrical problem, needless to say im glad i didnt. I know some one recently posted a thread on the little filter in the ML, are there any replacements for it? BTW RiceburnrEX is very helpful when it comes to trouble shooting 7th gen issues, thanks man!
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I wonder this topic myself. I never could get mine to work for more than a day or two, especially if it was cold outside. If you have an emanage you could use the boost cut limit instead though. I hope someone posts this info up.
Originally Posted by SODJAZERO
ok, i just removed that little filter and taped it up and my car works fine now..... So is the little filter nessesary?
I got cel too OK I been boosted for about 2-3 weeks now and my cel light finally came on. Car runs fine too. I know what you mean by car shutting off and on but its still fast. Is the missing link the reason my cel came on?
Originally Posted by SODJAZERO
were do i get check valves from?
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Originally Posted by andyman97
Any auto parts store. It's just a standard GM 1 way check valve. All you do is run a hose into the spot where the map plugs in on the manifold and get 3 vacuum t's that you can run in paralell and run a check valve off of them and pull the o ring off of the map and connect it to the top with another piece of hose, its really easy.
do you have a pic?
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Rep Power: 0 We ran the ML for 8 months, no MAP sensor errors at all. Car never shut off or anything. ML worked fine. We even used the voltage clamp on the E-Manage and retuned, but the car reacted far worse for power and such with the E-Manage voltage clamp. We then went back to the ML.
The filter according to Synapse is necessary. It is important to keep it clean. I cleaned ours once a month good with soap and water to make sure it did not become too dirty. Maybe that is the key. We never threw any MAP errors related to the ML.
BTW what code are you pulling from the ECU?
The filter according to Synapse is necessary. It is important to keep it clean. I cleaned ours once a month good with soap and water to make sure it did not become too dirty. Maybe that is the key. We never threw any MAP errors related to the ML.
BTW what code are you pulling from the ECU?
Originally Posted by 042dr
so how many people are using the check valves? Do you need to use a V-afc? w/these?
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Originally Posted by andyman97
Here is a pic of the check valves.
Originally Posted by andyman97
Two completely different things. All the check valves do is bleed boost from the map so the ecu doesn't register boost. VAFC controls injectors. Check valves are a cheaper, easier alternative to a missing link.
in your setup are you using somthing like dsm450's? I was thinking that maybe you'd still need the v-afc or a afc to control your fuel. Sorry if this sounds stupid. I'm new!!!lol
Originally Posted by andyman97
I'm running precision 440cc injectors. They are for a d16 fuel rail because I'm running a d16 intake manifold on my setup. I'm controlling them with an emanage.
Originally Posted by 042dr
I see...you said you are running 10psi? on stock internals? Also did you dyno tune this setup? Thanks
Originally Posted by andyman97
I haven't completed it yet. Getting downpipe and intercooler pipes done this week. I plan to go to the dyno next weekend after I get my pipes powdercoated. I'll have numbers then.
Keep us informed on your setup!
