russ98stang

I have a 98 gt and recently had the PI head swap. It sat for 9 months prior the swap. I got it back about 1 month ago noticed "the ticking noise" and also lack of power. It also started idling rough and would feel like it would misfire severly at about 1100 to 14000 rpm's. Well my check engine light came on and when i checked it, it came up emissions. I changed the egr valve and that didnt solve anything. After that i disconnected the power to the egr selinoid (or what ever it is) and the skipping and rough idle stopped as long as it is disconnected so i think that problem is a block egr pipe.
Now it runs smooth except at idle some times it dosnt sound exactly right. The power is still extremley low especially when the ac is on (dosnt want to accelerate hardly at all) and thats what im trying to figure out. I dont think the egr problem has anything to do with the low power issue but i was wondering if it could be a timing issue, or maybe even a clogged cat. I really have no idea so if anyone could give me some ideas it would be greatly appreciated because i feel like setting it on fire with a can of eather inside right about now.

silverstang1996

i had the same problem in my 4v motor except at 5k-6.8k, it was the sparks plugs that were causing the problem, so I'd check them if i were you, my plugs "gap" was too large so the guy i had fixng it got the right plugs and now it runs better than it did before

DIY

Could possibly be a tuning issue. Did you have it tuned after the swap?

russ98stang

no tune. Nothing was ever said about a tune in anything that covered the swap. Im gonna change the mid pipe tomorrow, maybe the one i got now (with 6 cats) is the problem. dont know though, just a shot in the dark. im putting a stock h pipe back on that has 4 cats. i got an x pipe, but im trying to sell it cause i hear people saying they dont like the sound it gives and you lose alot of torque.

DIY

The swap raises the compression of the motor. You should be using premium (91 octane or higher) gas to compensate for this. The pi swap improves power by increasing the amount of air that flows into the motor. Without a tune you run the risk of having a lean air/fuel ratio. This would cause serious power loss and engine damage. A tune would correct this by adding fuel to the mixture to correct the lean condition. The bottom line is that you would need a tune in order to see the performance benefits of the swap.

russ98stang

Well....crap...how much is that going to cost?

Fstanggt96

I had what sounds like the same problem as far as acceleration on my 88 5.0 GT. I blew a hole in the exhaust just before the mufflers and it was difficult to get the thing to faster than 70 mph. I put on a new cat-back and it ran fine.

russ98stang

What kind of engine damage are we talking about here b/c ive been driving it for about a month

oxfordgt

Its not a tune thing since it is happening at idle. The o2 sensors are used at warm idle to adjust a/f ratio. Swapping to PI heads will increase airflow but not enough to make you run lean and damage your engine at WOT. The stock tune has the a/f around 12.5:1, when you add PI heads it should change the a/f to 13:1 at WOT which is perfect for performance. Then only reason you would need a tune after a PI swap is to get it to idle correctly because of the cams.

Check your spark plug gap.

DIY

From what I read, the OP 's biggest concern right now is a lack of power. This would indicate a problem that is occurring at more than just idle. To the OP, when you check your spark plug gaps, take note of the condition of the plugs. If you don 't know what to look for, show the plugs to an experienced assistant at your local auto parts store. They should be able to read a spark plug for you.