Top end power loss !!!

[spdracr]

So as most you know I got the car together and it's running again.

Took it out for a drive the other night and did a pull on the highway. I noticed that after 4,500rpm the car doesn't make anymore power but it keeps on revving up though.

Things done to the car:
head slightly shaved
brand new exhaust valves
cut valve seats
head cleaned
new head gasket, head bolts and all new pulleys
Balance shafts deleted
5spd tranny swap

Checked compression and all the cylinders were in the range of 160-175 now I was told those numbers were too low but the compression was done without fully warming up the car

timing is also dead on

I can't think of anything else to check for

any thought or ideas would be great.

Thanks in advance

p.s. I'm available on aim all day so if you think you have a solution just shoot me a message on there. It's easier than checking the forum on my phone all day

[Galant Evolution]

^^comp should be around 190ish i belive... sorry for the off-topic but whats the benifit of the balance shaft delete??

[spdracr]

My friends Bryan and Nate just took it and got it inspected and then it on the highway and did a pull with it. They said they hit a 100mph at 4,000rpm in 5th gear and it stopped revving But it revs to redline in all other gears

they are gonna on the highway again and try to hit 100 in 4th gear and they gonna report back to me

[spdracr]

It let's the car rev up faster and gives few extra HP

compression is 190ish on a warmed up engine and my comp test was done on a cold engine

[qnz]

spark plugs gapped correctly?

[spdracr]

Yes they are all gapped evenly at .042. What's confusing is that I'm able to rev it to redline in all gears BUT the 5th gear. Would the speed sensor or any other sensor cause that ??

We used the Snap-on Solus scanner last night and it pulled no codes what so ever and all the numbers looked good. I'm about to swap out the ECU with another one but I don't wanna do that yet

[Stewi]

Alex do me a favor, your gonna need alot of open road for this....


Get it up to 4,000 in 5th gear, make sure your at WOT and press the clutch in fast and hold it down, see if the engine quickly jumps up and bounces off the rev limiter

[spdracr]

The check engine light came on and thry are scanning it as I type this. I will post the codes once they send them to me

p0421

[03-Galant-ES]

Who is Nate?

Ok let me see if I got this correctly.

All gears but 5th revv to redline, but dont make power after 4500. 5th gear will go to 4000 rpm and not higher?.

Were the exhaust valves OEM and you redid compression and it was c.190 on warm engine?

Did you get the CEL codes yet?

[spdracr]

03 galant. Read my post again. Intially the rpms would go over 4500 but as of today it stopped or maybe it didn't go past 4500 before I might be wrong

all gears redline without an issue but the 5th gear stops at 4000. I checked compression on a cold engine which gave me 160-175 and I never said 190 but those numbers are normal for a cold engine

code posted above

i previously had that code and never fixed it but it never caused this problem for me

[03-Galant-ES]

That code is warm up catalyst below threshold bank 1.

http://www.club3g.com/forum/performa...t-5-bucks.html

Post on club3G about it.

That doesnt seem to be the main problem though. I am gonna have to mull this over. I'll be back on later tonight as for now try to do Brian's test with the long runway.

[spdracr]

I knew what that code meant and I know its not the cause of my problem. I already have a post about this on club3g

[mko]

that code is just stupid. It has to do with the rear o2 sensor which has nothing to do with fuel trims. the rear o2 sensor is there as a part of the OBD2 system and it only tells the ECU that theres a catl. converter.

I got the electronic fix for the rear sensor and it has been working for me for the last 2 years. its cheaper than the spark fouler fix.

[troubled4g64t]

I have read somewhere in the past that, that code causes your car to go into limp mode it does not run at full power my wifes car had the same problem and it was the front cat needed to be replaced, did you remove the cat at all.

[Stewi]

I have read somewhere in the past that, that code causes your car to go into limp mode it does not run at full power my wifes car had the same problem and it was the front cat needed to be replaced, did you remove the cat at all.

If the car was in limp mode it would be there constantly based on load% and RPM, the fact the car redlines in 4 gears but gets held up in 5th makes me feel its not in limp mode. I had a 01 go into limp mode and it wouldnt go over 3000 RPMs or faster then 35mph.

[spdracr]

Stewi has been alotta help through texts and calls but he is still as puzzled as I am about this

the car is running stupid rich and the P0421 went away on it's own but code P0204 is pending on the scanner for cylinder #4

three things that I'm gonna check and possibly replace. Fpr, injector and the Cat

should unplugging the fpr make a difference ??

[mko]

three things that I'm gonna check and possibly replace. Fpr, injector and the Cat

should unplugging the fpr make a difference ??

unpluggin Fpr wont do a thing. the fuel pressure just wont be vacuum dependent and will be constant at around 35psi despite the amount of throttle

cat would be my best guess.

[03-Galant-ES]

I am still puzzled I had a few drinks with car buddies and we couldnt make sense one person said limp mode, but like stated it didnt seem like a limp mode.

I would check injector first. Probably easier to diagnose and if it isnt that like MKO said its likely the Cat

[bronxbombr]

did, anyone consider the trans to have a problem?

[WolfDog]

Could be the o2 sensor is cracked! May have happened inadvertantly during the work.

If the ceramic is cracked then the sensor is usless! It wont cause limp mode but it will cause the ecu to limit, it could explain a significant drop in power.

The ecu will limit varing amounts for a different number of reasons. Limp mode is literally that! it'll only limp home. Red line is out of the question.