Zelgadis69
Probationary Member
- 8
- 0
- Oct 30, 2003
About 9 months ago i had my timing belt changed at a shop. Before the change my boost gauge read around 17in hg at idle. After the change it read 7-8in hg. It doesnt really fluctuate but this is a horrible vacuume leak.
The mechanic said i had a cracked xaust manifold and the o2 sensor may be getting some messed up readings. I knew about this and thought it may have just gotten worse and didnt really understand how that would mess it up that bad but i just figured he was right.
First i replaced my boost gauge with another autometer thinking it may just be broken, still showed 5-10. Compression test showed 155-160 on all cylinders. So i replaced the manifold and gasket. didn't fix the prob. then replaced the o2 housing and gasket still didnt fix the prob. I just gave up on it until about 2 months ago when i thought i should really start trying to fix the damn thing. All the stuff i'm going to list did nothing to raise my vacuum at idle.
Replaced o2 sensor, ISC motor, replaced all vacuume lines then just decided to remove and cap all of them appropriately, replaced intake manifold gasket, replaced throttle body gaskets, replaced TB seals, replaced TPS, replaced BISS o-ring, intake leak tested at 20psi(heard nothing), replaced injectors with 450cc and injector seals, replaced ignition coil with spark plugs (gapped correctly) and plug wires, ignition timing and valve timing are fine... i think thats about it.
My car runs perfectly besides having a very light rough idle. No smoke out the back such as a rich mixture. Vacuume shows 21in hg under deceleration and my turbo spools fast as hell to 14psi(where it's set). My car seems as fast as it should be (wooping honduhs and mustangs easily despite losing 2nd gear on my a/t, planning conversion next month or so).
I am just completely stumped and dont know what else to do. I plan to get a leakdown test done soon and replace my vavles but i think i would have noticed damaged valves. Any input would be helpful. Sorry about the long post, just kinda in the typing mood i guess.
The mechanic said i had a cracked xaust manifold and the o2 sensor may be getting some messed up readings. I knew about this and thought it may have just gotten worse and didnt really understand how that would mess it up that bad but i just figured he was right.
First i replaced my boost gauge with another autometer thinking it may just be broken, still showed 5-10. Compression test showed 155-160 on all cylinders. So i replaced the manifold and gasket. didn't fix the prob. then replaced the o2 housing and gasket still didnt fix the prob. I just gave up on it until about 2 months ago when i thought i should really start trying to fix the damn thing. All the stuff i'm going to list did nothing to raise my vacuum at idle.
Replaced o2 sensor, ISC motor, replaced all vacuume lines then just decided to remove and cap all of them appropriately, replaced intake manifold gasket, replaced throttle body gaskets, replaced TB seals, replaced TPS, replaced BISS o-ring, intake leak tested at 20psi(heard nothing), replaced injectors with 450cc and injector seals, replaced ignition coil with spark plugs (gapped correctly) and plug wires, ignition timing and valve timing are fine... i think thats about it.
My car runs perfectly besides having a very light rough idle. No smoke out the back such as a rich mixture. Vacuume shows 21in hg under deceleration and my turbo spools fast as hell to 14psi(where it's set). My car seems as fast as it should be (wooping honduhs and mustangs easily despite losing 2nd gear on my a/t, planning conversion next month or so).
I am just completely stumped and dont know what else to do. I plan to get a leakdown test done soon and replace my vavles but i think i would have noticed damaged valves. Any input would be helpful. Sorry about the long post, just kinda in the typing mood i guess.
