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1989 GT Trick Flow Top end kit issues

Hi !
Read several posts on the topic, but threads are almost never updated with what was the cause of your issue

So, 1989 GT. Stock engine. Used to run a Powerdyne SC, auto trans. ( originalky a manual car )
Mods was BBK shortys, 3:73 gears, 24lbh injectors with matching MAF. SCT eliminator chip and upgraded fuel pump. Car was working perfect, with or without the Powerdyne.

So i decided to go Trick Flow top end kit, stage 1 cam, Wedge heads and street burner intake.
I reused all the electronic stuff, same injectors, same MAF,same TPS, same IAC and i slapped the stock TB on for now.
Attached all vacum connection as pulled off.

So…first start up went fine, surged for 30 seconds the died. Managed to get it to idle ok…but runs like crap….dies if i push gas pedal down or it goes all sluggish on me.
TPS is at 0.97, timing 12 set without the spout connected.
I also swapped back to T5 manual by the way.

Removed chip, tripple checked vacum and timing.
It starts fine but wont run or idle at all. Throttle respons is beyond sluggish. It will idle fine reving it past 1500-2000 rpms.
Vacum is good 14-16 at idle even it doesnt idle….grest vacum at 2000 rpm.
Pig rich.

Smog pump and A/C is deleted. EGR is connected to dummy plug.

Pulled codes:

KOEO only 11


13 - Normal idle not within specified range
18 - SPOUT circuit open
21 - Coolant temperature sensor out of specified range
33 - Canister or EGR valve not operating properly
42 - Fuel mixture rich
44 -Air management system inoperative
65 - Fuel control system not switching to closed loop
92 -Fuel mixture rich, fuel pressure high
94 - Secondary air system inoperative



Active Member
My vote is; you do have a vacuum leak.

If I had to guess... Which I don't like doing, I will guess at or just after the throttle body.

Just take a large can of brake cleaner and spray all the intake flanges you can get to. If the idle changes, that is at least... one of the leaks.

Then move on to the vacuum lines .

Good luck.
car starts perfect and idles nice at 750-800 rpm….no issues.
Throttle respons is good, revs nicely to 4000 rpm……but letting off the gas pedal it stalls……once or twice it actually didnt stall. If i shut it down by key, it will start right up and idle fine, if i rev it and it struggles and dies…..it will start right up but no idle.

ignition with spout out 12-13, idle fin at 750-800 rpm, vacuum at idle 12-13.
TPS 0.97- goes nice and steady to 4.3 from closed to wot.

codes are 11 at koeo

koer- 33,44,94…….they are all smog pump and egr…….egr is delete and smog pump not present.

i drove it 30 minutes, works ok on the road…..would expect more power on the TFS top end kit…..and will still stall now and then.
Just checking in to let you now my issues, it is all solved now.

Valves / Rockers was adjusted slightly to tight, but the Main reason was my MAF. Car runs like a B…ch now…..Thanks..