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1G Car barely starts, runs like ass

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trapdad

Proven Member
41
0
Mar 29, 2016
Lapeer, Michigan
So let me preface by saying I just installed a refreshed cylinder head. I haven't had the car running in months but everything worked before I started this. I dont have many mods, just a bigger turbo, fpr, lifters and that's about it. Stock 6 bolt. When I start it it sounds like it's running on 3 cylinders. Idles very bad but does idle. I've tried rotating the CAS little bits in either direction and it doesn't help much. Compression is similar across the board and all plugs are firing. What would make this happen and what other checks can I do?
 
Maybe the spark plug wires got damaged during the process? I pinched one unkowingly 1 time and had to replace.

Are the plug wires properly seated inthe coil packs? I had a shiiity set one time the the boot would slide around and when installed wouldnt push the contact in the coil pack all the way.

Corrosion in the coil pack or plug wire contacts?

Spark plug tip onthe wire side threaded all the way in? There is a little nipple type tip that sometimes backs out.
 
Oh and boost leak test it.... The rubber seals and orings around the injectors do get harder over time. I have removed a perfectly working set and installed on a different motor 3 days later and the injector seals wouldnt even holed 3 psi of boost. Vac is ~ negative 10-8 psi at idle so its possible your not getting a good seal and pulling in excess air in 1 cylinder.

Do you have a boost gauge or AFR gauge.
 
Oh and boost leak test it.... The rubber seals and orings around the injectors do get harder over time. I have removed a perfectly working set and installed on a different motor 3 days later and the injector seals wouldnt even holed 3 psi of boost. Vac is ~ negative 10-8 psi at idle so its possible your not getting a good seal and pulling in excess air in 1 cylinder.

Do you have a boost gauge or AFR gauge.
Tested all spark plug wires individually. Boost sits at -14 and it idles at 1000 rpm. The seals looked pretty good when I put them on.
 
Tested all spark plug wires individually. Boost sits at -14 and it idles at 1000 rpm. The seals looked pretty good when I put them on.

-14 is mos def in the normal range so its prolly not a leak then.

If you have spark and you have air it can only be fuel. Maybe you have a clog in an injector or the wires a loose?
 
-14 is mos def in the normal range so its prolly not a leak then.

If you have spark and you have air it can only be fuel. Maybe you have a clog in an injector or the wires a loose?
I ended up losing all the clips to the injector connectors but I don't think that would affect the connection. They're fairly on there.
 
-14 inches of vacuum at idle with a stock motor isnt too great. It should be around -18 to -20. Deff sounds like a vacuum leak. Did you replace all the gaskets and seals? (Manifold and throttle body)

Also double check your cam timing.
 
-14 inches of vacuum at idle with a stock motor isnt too great. It should be around -18 to -20. Deff sounds like a vacuum leak. Did you replace all the gaskets and seals? (Manifold and throttle body)

Also double check your cam timing.
I did double check my cam timing. Still good. Didn't replace the intake man gasket, but i will soon. Next time I work on it (wednesday), I'm going to let it get up to temperature and see if anything changes.
 
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