Car is a '99 FRC. Was stock before this (24k miles)

I just got done putting 1 7/8 catless kooks on to a 3x3 connection pipe. I put AI ported 799 heads on milled .030 with an ls2 gasket (to get closer to 11:1). I also decided to swap to an ls6 intake as well.

Went to start up the car and it won't hold an idle. It started at 1k, but then dropped to 400 and then died.

I also swapped in brand new ls7 lifters and new 7.375" pushrods. I replaced the injector o-rings and the intake manifold gaskets as well. My first thought was maybe a vac leak, but that would cause a high idle not a low one. Car is throwing no codes at all. My tuner suggested that the engine might be seeing so much more air now, that even though the cam is still stock, it may need a tune just to idle. Oh, I also removed the air tube but didnt turn it off yet, but I dont think it matters.

With that being said, I do remember parking the car with very low fuel so maybe its just out of gas? Car has been sitting for 2 weeks with almost no gas...that would be hilarious.

So anyway, just wanted to get this thread started before I actually put more gas in it and try again...please post any suggestions you have!

Here is what I was thinking:

1) Map sensor...I def plugged it in.
2) Maf sensor...also plugged it in for sure
3) Somehow the 02 sensors went bad? I doubt it though.
4) I added TR6 spark plugs..maybe it doesn't like them?
5) Maybe a spark plug wire is loose?
6) Bad fuse? I did pull the ign and both injector fuses to crank the car over..maybe I damaged one?

That is all I can think of right now...if anyone has any ideas let me know.

 

What do you have for a cam? My car started right up with a 228/228 and 36lb injectors and no tune. It started right up with a 402 and the same setup.

Can you feather the gas a little to bring the idle up?

Check to see the throttle body is clamped well to cold air intake. It won't idle with that thing loose.

 

Stock ls1 cam for now! I did heads/headers first because headers are very easy to install with the heads off so I figured what the hell.

Funny you mention that...I left the clamps off the power duct to throttle body connection. It was getting late so I just threw it on loosely and went to start it...didn't think that would matter at all in terms of idling. I will give it a shot tomorrow morning!

 

Wow - big headers, 3" pipes, and ported heads with a stock cam. I'd be looking at the mis-matched combo being the problem after you rule out the basics.

Not trying to be mean or point out the obvious - it's just the first thing that came to mind.

 

Nothing you have done to the car will cause this issue, it should idle fine. Re-trace your steps and make sure everything is correctly connected, O2 wires not crossed (front), etc. I keep a record of each thing disconnected when I work then check in reverse order during assembly. If no issues are found then I have one other observation.

Not sure if you measured for pushrod length, buy you selected pushrods that are 0.010" shorter then stock but took off 0.030" from the heads. Pull the driver valve cover and rotate the motor until the exhaust valve is just opening, then loosen the intake rocker and finger tighten to zero lash. Then count turns until you reach 22 lb-ft. If its near two turns or more you may be holding the valves open.

You could also do a quick compression check and determine if valves are not closing.

 

Exactly what I was thinking.

Well, stock is 7.400 right? I did measure and got 1 1/4 with 7.350 and 1 3/4 turns with 7.375. So I decided to go with 7.375.


Anyway, today I put in 1 gallon of gas, tightened the maf clamp, changed the plugs to stock, and put on all the wires again. No change.

When I pulled the plugs out, 3 of them were WET with fuel. 3 were black, and only 2 looked normal. The car feels like its not running on all 8 cylinders. I can keep it running by revving it, but the whole car shakes.

Still no codes. I did put anti seize on the 02 sensors...maybe some of it got on the tip of it and fouled it? I doubt it but who knows.

By the way, how do you cross 02 sensor wires? Seems like the length is barely just enough to reach its own connector. How would it even reach the other side? Maybe the 99's are different than later models?

Stock cam is temporary. People always add headers to their stock cammed cars with no problems. All the manifold and heads are doing is just adding even more airflow. True, its not the best combination for power yet, but the car should still run just fine.

 

O2 sensors in the front should be connected left header to left connector and right header to right connect. Connectors should be the flat connector, not square unless you used rear O2's.

Plugs are not the issue here.

Which plugs were wet and which were black?

Did you install the coils packs on the same side they came off of?

Do you have a spark tester?

 

Which 02 sensors matter? Is it the rears or the fronts? Because the rears you can definitely criss cross

Maybe they are backwards? I Hooked each one up to their corresponding side...

The one in the drivers side pipe, which is oriented like this / I stuck that one in the drivers side clip.

The one on the passenger side pipe, which is oriented like this \ I stuck that one in the passenger side clip.

Are you supposed to criss cross them since they are pointing that way?!?

 

The plugs on each side on the back cylinders were wet, driver's side worse than the passenger side as a whole.

I did install the coil packs on the same side they came off of.

I do not have a spark tester but I have no problem buying one...sears is right down the road.

Maybe I damaged an injector putting them in? Last time my maxima was running on 5 cylinders, it was the injector that was stuck closed.

 

When you pulled the injectors, did you leave them in the fuel rail and change only the lower o-ring?

Do you have access to an ohm meter? Can you check each plug wire for resistance? If not, if there is a cylinder you know it firing, carefully swap that wire with a cylinder that is not and see of the wet plug problem moves with the wire.

 

Ok looks like the rear 02's may be backwards on my car, would that matter? I found this archaic drawing and it looks like they should be criss-crossed.

http://www.jdmuniverse.com/z06vette/o2sensors.jpg

Yes, I can get an OHM meter.

When I pulled the injectors, I left the top part inside the fuel rail and only replaced the o-rings that go into the intake manifold.

 

Rears won't cause this, but yes fronts don't cross and the rears do cross. The fronts can cause problems.

 

Well the fronts are definitely in correctly...Maybe it is because the kooks have the bung farther away, but it is definitely impossible to criss-cross them. After work, I will still put the rears in the right place just in case.

 

If you haven't done so, double check the fuses especially those removed. Then I would check resistance on the spark plug wires.

When you crank it over, does it sound "normal" like you have compression?

 

Ill just replace the fuses just in case.

Its hard to tell because it literally only cranks for .3 seconds before it starts because all the fuel is pooling inside the cylinder.

 

Do you have access to a fuel pressure tester? If you turn on the key so the pump runs, you should see pressure come up on the fuel rail. When the pump shuts off after a couple of seconds the pressure should hold. If it drops, the injectors are leaking. Fuel pooling is an issue because it can wash the oil off the cylinder walls so the issue here needs to be sorted out first.

One other way to check this would be to pull the fuel rail up about 1/4" or so and watch for visible injector leaks when you pressurize the system (don't turn key to start). However, this is a risky move as there could be fuel spilling out of the bad injectors and you don't want a fire.

 

I think you can rent that tool at advance. I can rent a compression checker and a fuel pressure gauge. then check for compression, fuel, and spark after work.

I just visibly looked for leaks on the intake manifold and saw nothing though. Didn't smell gas either.

As for the fuel pooling...that is just a symptom of the problem that is causing my car to run like ****. Not really something I can fix without fixing the other problem first.

 

If you don't suspect a leak, then ignition may be the issue. Since you only disconnected the coil packs, plugs and wires and the wires are the easiest to damage, I would suspect them first and do a resistance check. Are these the stock wires that are a bitch to get off?

 

One thing I did notice was that only a couple of the header primaries were actually hot.

 

Yep, stock wires. They were actually very easy to get off. It is just hard to believe that that many wires would be damaged. I highly doubt it.