Can't get over 3.5k rpm, high knock...

[gijoe985]

Hey all,

First off, I am going to come right out and confess that this isn't on my DSM. It's my 3kgt VR4. But the guys on the 3si forum have not been much help and I feel that there are more people on here with more experience.

Anyway, here is what I've got happening..

Got this 3kgt, was supposed to have engine problems, tested good on leak down and compression, so I started it up. It idles alright, but cannot go above 3.5k rpm. It also has a high knock count. I get up to 26 or so. I can't find any vacuum leaks. I've sprayed around with carb cleaner, and had no luck. I rechecked the static timing and checked again with a light. Looks good.

I'm attaching a MMCd log to hopefully give someone smarter than I a clue.

And here is a link to my 3si post, maybe some more info on there.

High knock, won't go over 3k rpm, fuel trims, timing... - Page 2 - 3000GT/Stealth International Message Center

 

[wranglerunner22]

Sounds like its leaning out like a mother. First thing I would do is check fuel lines/filter/pump.

It also could be an electrical problem.

 

[gijoe985]

I could basically sum that all up with a fuel pressure test right? At least it'd probably cover all those fuel component bases...

 

[wranglerunner22]

I would say do that first. I am not sure of how that would work since there are different fuel maps.


When your at a standstill can you get past 3.5k?

 

[gijoe985]

No, all of the info above is sitting in park. I can't really step on the gas without getting knock in the 20s, so I'm not driving anywhere...

 

[BIGBLAZE79]

Those are bad arss cars, I wish I had one! Good luck man, wish I could help.

 

[killer_eclipse]

do you have any mods done to it? are you running any kind of fuel controller? as said above you are leaning out really bad and your fuel trims are way off as well if i remember corectly your fuel trims are like a 1g they are suposed to sit at 100 and if they are like a 1g then you are running rich at idle... but yet your o2 voltage is showing you are lean.... have you replaced your o2 sensor? fuel filter?

 

[gijoe985]

It does have a cat delete downpipe, MBC, and boost gauge. Also has vacuum delete. I don't think there is anything else done. Or at least that I notice.

I hope to check fuel pressure later, as long as I can find a place where I can tap in...

Also, the short term fuel trim shows rich, but just the other day it was sitting at 110%. So I don't know why it just had the polar shift...

 

[killer_eclipse]

i would start with checking fuel pressure and changing your o2 sensor

 

[gijoe985]

i would start with checking fuel pressure and changing your o2 sensor

Do we really think that the O2 is shot? I'd just want to be sure because I hate just throwing money at problems... (Particularly friends of mine who just start replacing things at random when problems arise)

 

[DSM91TURBOTALON]

Check the plug wires, my buddy had a 1990 talon tsi, couldnt get it passed 3k even when he floored it. He was getting lost of knock also. He put a new set of plugs and wires in it and it took care of the problem. Not saying that this is it, but its someting to consider.

 

[gijoe985]

Check the plug wires, my buddy had a 1990 talon tsi, couldnt get it passed 3k even when he floored it. He was getting lost of knock also. He put a new set of plugs and wires in it and it took care of the problem. Not saying that this is it, but its someting to consider.

Yeah, already did that, but I am going to try a power drop test... Make sure it is firing on all of them...

 

[gijoe985]

So supposedly this car was running fine, just had the engine rebuilt, and then it died on one of the first test runs. Considering the lean state, maybe the fuel filter collapsed? I need to do a pressure test, but have not figured out how yet. I have a t fitting that I could use to get in between two 3/8" fuel lines. Is there a place I could do that? I've actually never even seen the fuel filter on these cars. Underneath I assume...