Car is Running Horrible IDK why?

[AllGripNoSlipGSX]

1992 gsx 6bolt 13g turbo on 18 psi. Full 3" exhaust with a small fmic. Just did a full timing job. Compression is 150+ across the board. Car is running like complete shit. Set CAS to ~5* and tps is correct. Tps only reads about 4.2 volts. I'm running bpr7es plugs gapped to .028. Car ran immaculate before the tensioner failed, and I did all this work to it. I just want to know why its running so rough at idle. And under full throttle its the slowest its ever been. I need to do a compression test again, just to make sure nothing has changed. All the timing marks are lining up like they should, and the timing was set correctly. During the tear down of the top half of the motor I soldered in the CAS (b/c it was butt connected), I soldered in 2g fuel injector pigtails, I soldered in a coolant temp sensor pigtail and the pigtail close to it, and I soldered in an o2 pigtail. I am positive I soldered all of these correctly. Only thing I can think of to do is find another CAS/TPS/ECU. Idk? Vacuum at idle is between 13-15. The car will boost all the way to 20psi but settles at 18psi, but it is not going anywhere. It's like it is getting 25% of power from the turbo (idk if that's the best way to explain it). I just know that the car ran immaculate and had great power, then the tensioner failed, I had the cylinder head checked for bent valves, then reinstalled the head with an OEM tensioner and made sure the marks lined up mint (spun the crank multiple times). Any help will be greatly appreciated.

 

[yayabago]

thats alot to troubleshoot.. honestly u make want to go back to some stock stuff one by one for basic troubleshooting... another issue I have heard is the 3" exhaust - if u dont have a wide band could cause issues, do u have ecmlink? - do u get any codes - what size fuel injectors? psi leak test? vacuum test?

 

[AllGripNoSlipGSX]

I'm thinking I might need to remove the lifters and bleed them and reinstall. Idk. I am going to do a compression test ASAP and let everyone know where it is at.

 

[TSicktalon]

No idea what problems a 3" exhaust could cause.

I would start with the connectors you soldered in. Even though you know they're done correctly, triple check them. Also, do a BLT.

Bleeding the lifters won't help any of the issues you're having.

Your vacuum is borderline decent, I would suspect a small leak somewhere. The lack of power sounds like a leak as well.

Also possible you spliced a wire wrong. Maybe switched the +/- on an injector or bad grounds for some of the sensors.

 

[AllGripNoSlipGSX]

Well for the injectors it's a thick wire and a skinny wire. So I don't think I could've messed that up. The car ran immaculate before the tensioner failed. We checked the head out and it seemed fine (even though the tensioner had failed). I got a brand new OEM tensioner and set the timing mint and the car just is running like ass. I mean maybe the injector seals are bad and causing all the problems?

 

[Breezio69]

Id go toward something electrical. My knock sensor is broken at the moment and my car runs good, but when I hit full boost at wot it pulls all the timing. Boost gauge shows 18psi like normal, but it doesnt pick up like it did before the knock sensor went out.

Maybe something with the o2 sensor wiring you did is messed up, causing it to run either rich or lean and its pulling timing.

Also, at idle I'm at 19 vac with no leaks. My only problem is the knock sensor issue with timing.


And to top it off... I think despite looking over the head visually, if you didn't do a leak test you pretty much screwed yourself. I'm going to say you have a couple tweaked valves. Its very possible with even the slightest piston kiss.

 

[AllGripNoSlipGSX]

We had the head turned upside down with the cams lined up and used water to make sure they were all sealed. No water came out the other side. Idk?

Do the black wires for the o2 matter? Or are they both just grounds? I didn't wire it, a buddy of mine did, he claimed the black wires didn't matter.

 

[nwBryce89]

the first thing i would do is a boost leak test, which will let you know if the injector seals are leaking or anything else. check to make sure the cas is not 180 out.

 

[jhicks92]

leakdown test. eliminate anything and everything.

 

[Breezio69]

We had the head turned upside down with the cams lined up and used water to make sure they were all sealed. No water came out the other side. Idk?

Do the black wires for the o2 matter? Or are they both just grounds? I didn't wire it, a buddy of mine did, he claimed the black wires didn't matter.

When you test a head, you don't have the cams in. You lay it on its side with cams out, so all the valves are closed at the same time. If you lay it intake runners up then fill the intake runners with water. Let sit for a bit then note any water leaking out of the valves and which ones... rinse, dry out, repeat on the exhaust side. You have to plug the egr hole on runner 4 when you do the exhaust.

That's the propper way to do the leak test.

 

[Bud92gsx]

Flip the cas..Sometimes when you pull the head on the 6 bolts you install is 180 backwards..Try that its an easy 4 minute fix and come right back.

Why would u do 2g injector pigtails?

 

[AllGripNoSlipGSX]

My 1g pigtails were cracked and broken. The metal clips would only stay on 2 outta the 4. I switched to the 2g pigtails for easy removal and they didn't have any cracked or broken wires. I need to run a compression test and a BLT. The car seems like it wants to go above 4k rpm, but it definitely has no power in the low rpm's. I blew an ICP off while driving on the freeway today so I know it's boosting, it's just not moving out. Maybe knock sensor? Maybe the TPS isn't set up correctly? I lined the CAS up correctly. Set the "=" (equals sign) i will call it, to the timing mark and reinstalled with the cams TDC and the computer grounded out. It is at or around 5*. Could my TPS being dialed in wrong make it have a rough idle, and make me lose power? I mean when I drive the car sounds fine and all it just isn't going anywhere. Vacuum is still around 13-15 at idle.

bump

 

[AllGripNoSlipGSX]

Left after class today and headed back to Detroit. Showed up at my friends garage and we ran a compression check right away. Still 150+ across the board. So we checked the valve timing, we lined up the crank at TDC to see that the cams were about 4-5 teeth off. So, we pulled the front engine support bracket and went to work to reset timing and we realized that my other friend that gave me a hand with timing the car originally had placed the crank trigger plate on backwards.....so we got that straightened out and see timing and she ran immaculate. Car is back to her old self. Idk how it ran and drove with the crank trigger plate on backwards? I thought for sure that would have caused it to bend the valves. Only thing I can think of is that when we installed the head we lined up the cams beforehand, and maybe that made the difference. Any thoughts?