2G Terrible engine response

[Brandon Nicholson]

Hey tuners, I’ve recently picked up this 95 eclipse gs-t automatic as a fun project/dd for my sister, it’s all stock except for rims and cd changer,

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The issue I’m currently having is that the engine has very sluggish performance driving around town. Like no power at all It feels like ignition timing is being pulled or there is a trailer attached . I can’t really blip the throttle either it will take the engine a split second to react to throttle change, no snappy ness. It idles smoothly but higher then usual. (1200rpms) and if I drive around town for a short time the exhaust manifold will glow red hot.

So far I’ve looked/changed the following:
Fuel filter
Plugs
Removed downpipe to see if cat was clogged
Inspected timing marks
Boost leak tested which revealed biss and tb shaft seals had small leaks

the car initially threw camshaft position sensor circuit A CEL (I believe I don’t quite remember) but I cleared it without thinking of getting the actual code

I’m assuming the tb leaks are what causing higher then usual idle but the very poor performance still has me asking questions, could it be cam/crank timing? I have checked by setting the motor at TDC and looking at the cam gears they appear to be in time. I did have to make sure the crank was 100% lined up with the case for the upper gears to line up

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[spyderdrifter]

Those wheels... looks good otherwise. Do a boost leak test to find all those little irritating leaks. As for that code, it might be a good idea to replace the cam sensor if that was the actual code thrown. Based on your pic of the harmonic balancer, it does look like timing was advanced. Do you know any historic info regarding the car's maintenance? My guess is maybe the timing belt has stretched a little over time, or the timing tensioner has weakened. Just thoughts.

 

[ErikTande]

Small throttle body boost leaks won't cause a stock cast manifold to glow red just driving around town. You've got to be doing some serious pulls to get those things to glow, so that's the biggest lead on what the problem is. Post a video of the engine revving it a little.

I would say clogged CAT, but if you already took the downpipe off then it has to be something else. Any blockage in the intake? Turbo looking ok?

Nice find!!

 

[Brandon Nicholson]

Those wheels... looks good otherwise. Do a boost leak test to find all those little irritating leaks. As for that code, it might be a good idea to replace the cam sensor if that was the actual code thrown. Based on your pic of the harmonic balancer, it does look like timing was advanced. Do you know any historic info regarding the car's maintenance? My guess is maybe the timing belt has stretched a little over time, or the timing tensioner has weakened. Just thoughts.

I agree those rims are awful. As for how the car was maintained I don’t have concrete records of major servicing but they did state that it was regularly maintained at a shop and that whenever it needed something they got good parts, the turbo looks fairly new aswell as a new radiator, The timing belt does have an oem part number so I’m only assuming it’s original.

 

[Brandon Nicholson]

Small throttle body boost leaks won't cause a stock cast manifold to glow red just driving around town. You've got to be doing some serious pulls to get those things to glow, so that's the biggest lead on what the problem is. Post a video of the engine revving it a little.

I would say clogged CAT, but if you already took the downpipe off then it has to be something else. Any blockage in the intake? Turbo looking ok?

Nice find!!

Thank you!! And yes the intake pipe and turbo appear to be in good condition, I’ll get a video of it revving here soon

 

[spyderdrifter]

How many miles on the clock?

 

[Brandon Nicholson]

How many miles on the clock?

140k miles

 

[spyderdrifter]

Way too many if that is the original belt for sure.

 

[Brandon Nicholson]

Way too many if that is the original belt for sure.

I definitely agree I’ll be changing it no matter what
I also went ahead and took off the exhaust manifold and o2 housing to see if possibly the sealing ring was blocking the hot side but it’s all clean, turbine looks in good shape but there’s a huge crack in the manifold

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I’ll be pulling off the timing cover next and redoing the timing with a new belt to see if that helps

 

[chrysler kid]

That crack is probably causing all of your problems

Also on a bone stock car the throttle response is really hurt by the stock rubber intercooler piping. If you can budget it, a new set of aluminum pipes on eBay is usually around $125 and they will make a noticeable difference in boost response and throttle response, same with the stock blow off valve. The stock blow off valve can cause a boost leak so make sure you test the old one

 

[spyderdrifter]

Nice exhaust leak for sure.

 

[ErikTande]

That crack is probably causing all of your problems

How so? I would think that crack would be the RESULT of the insanely high exhaust manifold temps, rather than the cause of it. Or are you thinking the crack is leaking and causing turbulence or something causing the high exhaust manifold temps?

But yeah, either way I'd replace that!

 

[pauleyman]

What vacuum is the car seeing? Exhaust clog could be a problem. You dropped downpipe but what did you see? How did you inspect? Did you check the exhaust flex also? I've seen them collapse.
I also don't trust using the harmonic balancer to check mechanical timing.

 

[Canadian_CD9A]

Flex pipe was going to be my suggestion, I've seen a few fail and become massive restrictions.

 

[miguelmcv]

You mention is in a stock form, you checked the downpipe but what about the catalytic converters, did you inspected too?..

I have had some clogged on me and some gets noisy but others don’t, I would check that out.

Just to mention, autos feel heavy on the take off compared to manuals, I have both of them and I love the manual better then the auto.

 

[JeffGS-T97]

An exhaust leak in the manifold would cause alot of issues due to exhaust velocity loss before entering the turbo housing hurting the spool up of the turbo itself. 02 levels will be effected as well since the 02 sensors are after the turbo. The escaping 02 and gas fumes are then not metered by the 02 sensors. The AFR will become unbalanced causing loss of even more power and driveability.

 

[Brandon Nicholson]

What vacuum is the car seeing? Exhaust clog could be a problem. You dropped downpipe but what did you see? How did you inspect? Did you check the exhaust flex also? I've seen them collapse.
I also don't trust using the harmonic balancer to check mechanical timing.

I have not hooked up a vacuum gauge yet since it’s currently down to replace that manifold. As for the exhaust I only loosened the flange from the o2 housing to the downpipe and left a 1/2inch gap in between but that made no difference, maybe I need to fully take it off but it’s just super loud . I’m also going to be taking off the front cover and inspecting the marks instead of using the crank pulley

 

[Brandon Nicholson]

An exhaust leak in the manifold would cause alot of issues due to exhaust velocity loss before entering the turbo housing hurting the spool up of the turbo itself. 02 levels will be effected as well since the 02 sensors are after the turbo. The escaping 02 and gas fumes are then not metered by the 02 sensors. The AFR will become unbalanced causing loss of even more power and driveability.

I went around the block today after fixing all of the exhaust leaks and brought an obd2 scanner and I noticed very quickly that ignition advance was not moving past 5degrees! Even cruising around I know that it should be in the high 20s, I’m now even more stumped though I do believe this is what is causing my glowing manifold and no power situation, could a knock sensor be so bad that it would pull that much timing? Or possibly the wiring for the ground connector on the ecu may be messed up. I’m really not sure

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[jakelandry]

This thread is atrocious. It looks like your timing diagnostic pigtail is grounded.

 

[Brandon Nicholson]

This thread is atrocious. It looks like your timing diagnostic pigtail is grounded.

I’ll make sure to check that.. its a brown plug on a 2ga correct? And sorry if the thread is atrocious it helps me since I’ve never had this issue on my other dsms

 

[jakelandry]

I’ll make sure to check that.. its a brown plug on a 2ga correct? And sorry if the thread is atrocious it helps me since I’ve never had this issue on my other dsms

No you seem to be one of the more competent people in here. My comment was directed at the fact that people actually suggested the stock intake piping or exhaust crack was your issue.

The fact that the timing is locked at 5* leads me to believe it would be either within the ecu or the plug was grounded. Provided the tune doesn’t have something wonky going on with anything that controls timing, that plug is the only thing to my knowledge that will lock the timing.

I believe it is the brown connector. It should only be one wire. It is possible that someone messed with the wires as they go into the ecu also. It’s a popular place people tap into wires for sensors, alarms, Turbo timers, etc.

 

[Brandon Nicholson]

No you seem to be one of the more competent people in here. My comment was directed at the fact that people actually suggested the stock intake piping or exhaust crack was your issue.

The fact that the timing is locked at 5* leads me to believe it would be either within the ecu or the plug was grounded. Provided the tune doesn’t have something wonky going on with anything that controls timing, that plug is the only thing to my knowledge that will lock the timing.

I believe it is the brown connector. It should only be one wire. It is possible that someone messed with the wires as they go into the ecu also. It’s a popular place people tap into wires for sensors, alarms, Turbo timers, etc.

I had a spare 97 ecu laying around for testing purposes and I decided to throw that in aswell as disconnect pin 52(ignition timing adjustment connector) at the ecu just to be sure it’s not grounding somewhere through the engine harness. sure enough after swapping plug wires around and firing it up timing moves freely again! Power and response is back even for stock form it actually gets out of its way now

 

[pauleyman]

So how do you know if its ecu or harness?

 

[Brandon Nicholson]

So how do you know if its ecu or harness?

I’m not sure to be honest with you, but I can do a process of elimination by putting pin 52 back in the 97 ecu and seeing if it locks timing again. If it doesn’t then I can be sure the 95 ecu is the culprit correct?

 

[pauleyman]

I’m not sure to be honest with you, but I can do a process of elimination by putting pin 52 back in the 97 ecu and seeing if it locks timing again. If it doesn’t then I can be sure the 95 ecu is the culprit correct?

Yes that is what I would suggest. Sounds like you're on the right track