I need urgent help with an LD9
I have a 97 Z24 that has recently spun a rod bearing, we took that LD9 out, and replaced it with an LD9 out of a 97 Malibu. The motor has 109k on it and we replaced the rod and main bearings, oil pump, water pump, and timing set. EVERY sensor off my old LD9 that had 115k on it, went on this new motor, the intake, throttle body, injectors, practically everything on the outside of the motor. My old LD9 was an absolute POWER HOUSE for a pretty much bone stock LD9. The only problem I had with the old LD was it studdered a little on idle, but cleaning the throttle body fixed that, and it threw a 404 and 405 check engine code which is for the EGR valve. Had it on a Snap-On scan tool and the EGR works beautifully but it still throws the code. Now my delima is, this new LD has half the power the old one did, and surges when the throttle is completely closed, and feels like the engine is just rocking back and forth really hard, but all the motor mounts and trans mounts are solid. It has no vacuum leaks, and the only modification the car has is an after market cat back. Any suggestions? I have to travel 600 miles with it Sunday. Need help ASAP!
The car doesnt really hunt for the idle, it idles great, smooth and steady. When letting off the gas say Im in 5th gear at 60, and I want to start slowing down and downshifting, I let it fall to 55 and it surges like I said in the previous post, and it does that in every gear between 2k rpms and 3k rpms. Like I said it has NO pull. Before, any hill, hit the bottom in 5th running 30, and it would pull all the way up and gain speed. Now its ON THE FLOOR in 4th at 55 maybe. Hell it wont spin the inside tire on wet pavement going around a corner anymore in 1st, it used to spin both tires on wet pavement and you could shift throught he gears up to 3rd. Has a major lack of power.
you probably have the cam timing a tooth off
well thats what we were thinking, but when we took the timing chain adjuster out and did the timing set, the cams didnt move. Maybe the crank moved, I have no clue. But is there anyway to check that without taking the timing cover and stuff off? What I got told was that the ECU controls the timing advance and retard, there could be a possiblity I was misinformed. I will have some time when I get back to college. I know the timing would be a hell of a job in a college parking lot.
and to be honest if Im going to @!#$ with the cams Im going to do a secret cam swap.
Setting the timing correctly and doing a cam swap are 2 different things. The crank or cams do not have to move for it to be off. I have had the chain jump I tooth before when you apply tension to it.
Did you turn the crank a full revolution and then check the timing marks after you set the timing?
FU Tuning
I didnt install the tensioner, so I am unsure if they did or not. How difficult is it to return the timing?
Curtis Whitehill wrote:I didnt install the tensioner, so I am unsure if they did or not. How difficult is it to return the timing?
If there is no tension then the car would not run at all. Get a haynes manual. It has the steps for doing the timing. This can be done with the motor in the car. Probably take a couple hours.
FU Tuning
My sunfire gt did the same thing, it turn out the timing was off by a cunt hair. After i checked it all out twice she was off a tooth. Check your timming again and yyou might find your problem.
no matter how ya look at it , its gonna be a bitch to do , gm didnt make it easy
first time i did a 2.4 i had it a tooth off , luckily i noticed it when it was still out of the car
[quote=97cavie24ls(™)]no matter how ya look at it , its gonna be a bitch to do , gm didnt make it easy
first time i did a 2.4 i had it a tooth off , luckily i noticed it when it was still out of the car
If yu have experience with it it can be done in like a hour.
I know the first time me and my friends every did a 2.4 in the car it took us hours just to get to the timing chain to mess with it. Those 25 10mm bolts kicked our butts. Now it is a different story.
FU Tuning
Update.
Car still runs like sh*t, now it acts like it hits a brick wall at any rpm when its cold and sometimes when its warm. No pull until it hits 4500 rpm then it still has very little top end pull. Recently the car has had a new pcm installed (with crank sensor relearn) and plugs. Also the EGR has been fixed it was sticking open. The car has speratic Idle until warm. It also has an intermitant misfire on all 4 cylinders and runs rich as balls, Im talking like 17 miles to the gallon rich as balls...Have checked fuel pressure, fuel injectors, ignition coils, and cam and crank senors. Fuel pressure is good. Injectors, ignition coils and the cam and crank sensors have all been oscillascope tested with the supervision of a GM certified technician. The PCM was bad, that has been replaced and I did a crank sensor relearn with a Tech2 and it now detects that the car has a misfire, where as before it would not. I am really at a loss with the car at this point, I personally believe that something mechanically is causing the misfire, although I could be completely wrong. Looking for any insight that anyone has. Thanks.
The timing has not been checked yet.
Check the timing already!!!! Also check the vacuum hose going to the MAP sensor.
Currently #4 in Ecotec Forced Induction horsepower ratings. 505.8 WHP 414WTQ!!!
Currently 3rd quickest Ecotec on the .org - 10.949 @ 131.50 MPH!!!
I'm going with the timing being a tooth off.
PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO
How many more people do you need to tell you to check the timing before you do that?
You could have easily done that by now with all the work u just did do it.
if you're getting a P0300 code (random/multiple misfire) after doing timing chain work, you most definately are off at least a tooth. tear it apart. its retarded easy to set timing on these motors. both cam gears lock in place. theres an extra hole in the cam gears, and in the cam towers (behind the cam gears) to do so. insert one of the ignition cover bolts through the extra hole in the gears into the hole in the cam towers and it locks the cam in place. both cams will lock in place. once you lock both gears in place remove tension from the chain and lineup the dot on the crank gear with the mark on the timing case (easier to do this with the tensioner removed). apply tension to the chain with the tensioner, remove the bolts in the cam gears, rotate the crank 2 times then lock the gears in place again. check to see if the crank mark still lines up. if it does you're all set. if not then remove tension and lineup the mark again. rotate and check again as needed. close it up, put the bolts back in the IDI cover and fire it up. it should feel 100X better if the timing is right.
ive had the timing case apart for this more times than i'd like to admit.. fastest i got it down to with air tools was like 2 hours, apart, set and back together. slowest with air tools was around 4 hours. it can be a pain in the ass, but IMO it sounds like it needs to be done.
sounds like tuning may also help correct this (if timing is not off)
Exhaust Cam was off by one tooth. MUCH BETTER!
