kato89GTA

Guys, need your help, I installed an Edelbrock High Flow TPI intake and SLP runners and the car has not run right since.

Here's the problem:

1) Running rich (Badly)
2) Idles fine (surges a little) Boggs down real hard when increasing throttle from idle and pops (sometimes) into the intake.

Here's what I've changed to it to try and fix:

All sensors with new to include CTS, EGR valve, MAS, MAT, TPS, IAC, new Fuel injectors, Knock sensor, fuel pump, fuel filter, Ignition control module, electronic spark control module, cap, rotor, new plugs, wires, coil, distributor, changed ECM, fuel pump control relay, O2 sensor, fuel pressure regulator, EGR solenoid, oil sending unit, verified and set base timing at 8 degrees BTDC, replaced all rings in all cylinders, new trickflow heads with 3/4 turns on rockers after zero lash. Made sure there were no exhaust leaks between y-pipe and collector especially near 02 sensor. Verified vapor canister purge solenoid is working, blew air through vent line by vapor canister back to tank (no clogs), Cleaned the fairly new BBK 58MM throttle body, resealed the top and base plates of the throttle body, verified IAC is working via winaldl, verified injectors were not leaking by pinching off return line,........I think that's it, and the damn car still has the same problem.

So to sum it up, I now have a new ignition system, new fuel system, a new intake system and I feel I have done everything I could possibly do to this car to get it to run right and have failed.....can someone please tell me if im missing something?

Thanks.

vetteoz

iTrader: (13)

https://www.thirdgen.org/forums/tech...s-dumbies.html

kato89GTA

Thanks for the quick response, I've been using winaldl to data log and I have a code scanner, the ecm is not throwing any codes.

The only odd thing is that winaldl is reading "overdrive on" when the car is parked and at idle. Is this supposed to happen?

eseibel67

Wow that's quite a parts list.

It started after the intake parts swap, so you gotta thnk it's related to something that got disturbed. I know you have a new regulator, but is the fuel pressure within spec both with and without vacuum?

Also, popping through intake might indicate a worn exhaust cam lobe. Unlikely because these motors use roller lifters, but might be worth checking.

kato89GTA

Thank you sir for your help! Fuel pressure is good with and without vacuum. Its about 50 with vacuum and a little higher without. I pinched off the return line and the system holds 99 PSI constant and does not bleed down at all.

I found something odd about the intake when I first installed it. One of the runner lower rear bolt holes on the drivers side was leaking antifreeze when I refilled the coolant system with the runners removed. I didn't know if this was normal or not (seems obvious now) so I sealed the threads on the bolt then installed the runner and the leak stopped. After that I noticed that my radiator coolant level kept dropping but there were no external leaks anywhere.

I spoke with Edelbrock tech guy who was not helpful at all. He was convinced that my car needed to be tuned. He didn't want to hear anything else about it until I told him about the lower rear drivers side runner bolt hole was leaking antifreeze. He told me that it should not be doing that which to me indicated a manufacturing defect.

I removed the intake then took an air hose and blew air through the bolt hole and sure enough, I felt air blowing into the rear coolant crossover galley at the back of the intake.

I could be wrong but my theory is, coolant was somehow leaking into the runner and down to cylinders and tweaking the air/fuel ratio that was being read by the 02 sensor. This is probably why my radiator coolant level kept decreasing but there were no external leaks anywhere and the car smoked badly.

The 02 sensor is at the base of the header on the drivers side where the leaky hole is. This somehow may have been causing the computer to richen up the fuel mixture to the engine or causing it to bog down significantly. I also had fluid SPRAYING out of the tail pipes that didn't smell like gas.

I called a summit tech rep who was very helpful. I explained the problem to him and he stated that if its losing coolant through the runner bolt hole then it also could be losing vacuum. This vacuum loss would cause a lean condition which would then cause the computer to richen up the engine. You would think this would throw a code....it didn't, but it makes sense.

Of course, through all of this, the ECM didn't code out for anything at anytime. It took a long time for me to brain crunch this problem, not sure if a new intake will fix the problem, but I sent the intake back to summit yesterday for an exchange....fingers crossed!

I have new heads and new head gaskets and no coolant in the oil and no oil in the coolant so I know the coolant loss is not coming from a defect with the head gaskets. Lastly, I think the popping in the intake could be caused by the ecm messing with the timing causing an insufficient fuel burn and fouling the plugs. I believe any unburnt fuel in the cylinders could be firing off simply by the heat of the cylinders. This is probably why the popping is not a consistent problem in the intake.

I have owned this car for 18 years, I do all my own maintenance on it and put it in as many car shows as I can. I have had problems with it the past (25 years old, go figure) but always have been able to figure it out on my own. I usually never post on tech boards but I can assure you, this problem had me really scratching my head and pissing a lot of money away so I had to go external.

I sincerely thank you for your reply and I will post an update once I install the new intake.

Again, thanks for your help!

eseibel67

Your fuel pressure is too high. Should be 40-47 PSI without vacuum, lower with vacuum applied.

There's no way your lower runner bolts should be into a water passage. See what the new intake brings.

kato89GTA

I've always had the car running at that fuel pressure. ...I will lower it and see what happens. Thanks for your reply!

Mongoose

iTrader: (2)

Subscribed as I am preparing to install this same intake.

Mongoose

iTrader: (2)

I just looked my intake over and noticed a small hole that looks to have been drilled in each of the intake runners,I'm thinking this is for egr....can anyone confirm this as I don't recall seeing a similar feature on the OE versions I've seen.

92crimsonRS

i had an issue with those runners not allowing my injectors to fully seat causing a huge vaccum leak just as you described. i would check to make sure everything is sitting flush and theres nothing keeping a gasket from sealing. also some gasket sealer might help as well.