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2G High boost, slow acceleration

garytheberry

Probationary Member
6
0
Jul 1, 2020
New Braunfels, Texas
Hey guys, I have a 1999 eclipse 4g63 and I’m having an issue where it makes boost easily but barely accelerates. When I hit the gas the boost skyrockets along with the rpm but I’m not going anywhere. By the time I get to third gear I have zero acceleration and at that point I can’t get the boost or rpm to go any higher. This all started happening immediately after I filled it up with gas for the first time. I had just been putting 5 gallons in at a time because the tires wouldn’t hold air to go any distance. Any ideas what is going on?
 

1990TSIAWDTALON

Moderator
9,673
5,510
Nov 14, 2013
Independence, Kansas
His profile isn't filled out or we would know if it is a standard or an auto he is referring to. If it is an auto, check the trans fluid level when warm and in NEUTRAL.
 

1990TSIAWDTALON

Moderator
9,673
5,510
Nov 14, 2013
Independence, Kansas
I saw that too @benspilk09 and made me wonder if it was a stick or auto car.
 

El Cuervo

15+ Year Contributor
575
25
Nov 7, 2004
Omaha, Nebraska
Well, since we don't have much information on the vehicle, but only what's on the first post, the only option that we have is to speculate, process of elimination and to just play the guessing game till the opener submits more info. So with this said, these are my opinions. I'll assume that it's a manual. So there is 2 very quick guesses here which are: boost leaks and slipping clutch.
Can it be a boost leak? Well, it can have boost leaks yes because they are very common but, he is building boost after all. At what rpms? Who knows but he is building boost after all. So let's move that aside for the time being.
How about slipping clutch? Ok it's possible because of the high revs and not going anywhere. However, I think he would have mention that he would be smelling clutch if there was alot slip but most important, he was building boost after all, which means that the engine was under enough load to build that X amount of boost that he claims.
So is it clutch related? Maybe or maybe not?
How about: timing. There is boost after all.
Maybe he has knock and is regarding enough timing that the car will feel excessively sluggish at a higher rpm and boost.
It's a possibility . Yes there is no logs or anything. We are simply going by what we have in the first post and our own personal experiences.
 

jed344

Supporting VIP
1,179
284
Jan 10, 2008
Waterville, Iowa
He did not even say if he has gauges or if his "building" boost is via the joke factory gauge going up. So not enough information to even give any real guess. I have tuned cars that had bad knock sensors as well as cars that have seen 7+ degrees of knock retard and even in stock form they still accelerate.
 

1990TSIAWDTALON

Moderator
9,673
5,510
Nov 14, 2013
Independence, Kansas
Watch it be an auto low on fluid.......ROFL
Hope to get more info.
 

El Cuervo

15+ Year Contributor
575
25
Nov 7, 2004
Omaha, Nebraska
Watch it be an auto low on fluid.......ROFL
Hope to get more info.
. Right!!! For all we know, he might be just revving it in neutral in his driveway to see if he can actually build boost. Who knows, the faint sound of a turbo on neutral does have a nice tone to it.
Maybe he got bored and for a moment, let his imagination run wild and pretended that he was in an airplane or space ship that is about ready to take off. Just saying.... hahahaha
 

1990TSIAWDTALON

Moderator
9,673
5,510
Nov 14, 2013
Independence, Kansas
I always make the appropriate noises too when I do that.......(makes turbo and BOV noises) :shhh:
 

El Cuervo

15+ Year Contributor
575
25
Nov 7, 2004
Omaha, Nebraska
Well, I'm glad I'm not the only crazy one here. That makes 3 of us, including the opener by default LOLLOLLOL.
 

garytheberry

Probationary Member
6
0
Jul 1, 2020
New Braunfels, Texas
So I did a boost leak test. I hooked up the compressor to the turbo inlet with 20 psi and there were several leaks on the coupling and I did fix those and the car runs a lot better. However, there is a spot on the bov that is leaking. There are two nipples coming out of it, one of which has a hose attached to it and the other doesn’t. The nipple that has nothing attached to it is leaking. Is there supposed to be a hose connected to it? The car is a manual and I really don’t think the clutch is slipping as it shifts smooth and engages quickly. Also I did a few tests on the Wastegate actuator and it does not hold pressure.
 

garytheberry

Probationary Member
6
0
Jul 1, 2020
New Braunfels, Texas
So I did a boost leak test. I hooked up the compressor to the turbo inlet with 20 psi and there were several leaks on the coupling and I did fix those and the car runs a lot better. However, there is a spot on the bov that is leaking. There are two nipples coming out of it, one of which has a hose attached to it and the other doesn’t. The nipple that has nothing attached to it is leaking. Is there supposed to be a hose connected to it? The car is a manual and I really don’t think the clutch is slipping as it shifts smooth and engages quickly. Also I did a few tests on the Wastegate actuator and it does not hold pressure.
Also the stock boost gauge is on there so it’s basically useless
 

jpmxrider489

Supporting VIP
2,386
130
Apr 4, 2010
pittsburgh, Pennsylvania
Hey guys, I have a 1999 eclipse 4g63 and I’m having an issue where it makes boost easily but barely accelerates. When I hit the gas the boost skyrockets along with the rpm but I’m not going anywhere. By the time I get to third gear I have zero acceleration and at that point I can’t get the boost or rpm to go any higher. This all started happening immediately after I filled it up with gas for the first time. I had just been putting 5 gallons in at a time because the tires wouldn’t hold air to go any distance. Any ideas what is going on?


After reading most of this post, I figured I would add my personal experience. A clutch slipping would feel like a stutter. The car wouldn't want to move but rpm and boost can go up. I have felt this with a act 2100 and 2600. I'm currently on the 2900.

Have you replaced plugs and wires? I was chasing a issue similar, it ended up being a bad coil. We found it by stress testing the coil. One coil was arcing at idle that you couldn't see. The other coil was arcing at 25psi. Apparently I had all the bad oem coils on the east coast LOL.
 
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