I have to remove the upper intake to inspect for leaks, iam getting severe pinging, i mean its like running 3 octane fuel, i get it around 2k rpm under load.I use 93 octane gas, tested the maf, replaced fuel filter, checked for vac leaks , i hear a his behind the intake, so i dont know if its just the air rushing through the intake or i got a leak back there, Is there anything that might hold me up when removing the intake, also can i reuse the gasket ?

 

it is not advisable to re-use the gasket. They are cheap and I would replace it.

 

Meh i called Autozone and Advanced Auto Parts, they dont even have a listing, Napa has the set for $8 but got to order it.

 

What about O.E.M.?

 

i have to drive nearly 60 miles to the nearest dealer, i live in sticks

 

Call Dave B and order one. the cost of shipping is probably less than the gas from a 120 drive with a pinging car.

 

If you hear the hissing right near the firewall, you could be hearing the PCV valve passing air.

My 02 has a slight hiss right near the firewall where the PCV is and its normal.

 

Use the duck/quack theory.......If you can hear it, and it sounds like a vacuum leak.......it's probably a vacuum leak.

 

I dont have a pcv valve the line is capped off and the hole is plugged, it cant be that.

 

I also agree that one should not reuse an old gasket, and if your going to take off the upper intake you might even want to consider NWP spacers http://www.nwpengineering.com/Phenolic_Spacers.html

and eliminate the need to change gasket improve your air flow and help keep the engine cooler. Have every done a seafoam treatment to help remove any carbon inside the engine perhaps this may help you and don't forget to do the oil change following the seafoam cleaning.

 

Yeah i did the seafoam, i ran lucas, i ran a fuel treatment thru , nothing stops the severe pinging.i even removed the fuel line and ran the car off a special injector cleaner, it was some pressurized can and the car ran till it was empty, i still think its a vac leak but iam not positive. plus $225 is abit steep for a spacer at this time.

I was looking at OEM plugs and they offer 2 types , PFR4G-11 and PFR5G-11, iam gona try the 5g since its a colder plug, that might help. i dont know whats in there now, i think there bosch plugs.

 

The cooler plugs may help you, the NWP spacers was just a thought seeing your going to be taking things apart, but yes they are pricey.

 

Well first you need to figure out what the problem is. Is it detonation? Or just a rattle? Loud pinging around 2k seems like a rattle to me, and not detonation, as detonation usually covers a much larger rpm range. 2k rpm to redline, for example "usually" being the key word.

I'd also try putting the PCV valve back to how it was, because those caps could be leaking. If you still have the hissing noise, you can use some starting fluid to spray around the manifold. If the engine picks up speed like the throttle was "blipped" then you have a vacuum leak.

These cars are getting older, so take a look at the heat shields, look for loose bolts/nuts and eliminate a simple rattle that is sometimes mistaken for detonation. If you rule this out, then you can search out for signs of detonation.

The proof positive way to find out is to check the spark plugs. If they look like they've been sprinkled with salt and pepper, then you've got a detonation problem. Check the front 3 first since they do not involve putting the manifold. If you're suspicious, then go ahead and replace all 6, and yes you need a new plenum gasket. Don't put Bosch plugs in there either (again!).

If it's not a loose bolt, or detonation, it could be internal. Use a long screwdriver and hold the handle up to your ear, and put the other end on various parts of the engine. It works as a stethoscope and can help you narrow down the area that has trouble. Then you'll need to figure out how much you like your car

 

I heard somewhere that you can spray propane gas around the intake and if the engine rpm surges, you found the leak.

 

Trust me its pinging, i cleared the codes today and looked at the datastream, nothing looks out of place, but since i cleared the codes the pinging got severely worse, from 2k over 3k its major bad, i had to nurse it home under 2k........... i bought new intake gaskets, iam gona pull it apart in a few hours and inspect everything, its so bad iam afraid to even drive it.

 

replaced the gasket now it runs sloppy, and it surges sometimes while driving, it just dont seem right now.

 

Which gasket? Did you change plugs?

 

It's running "sloppy" and it surges, but is it still pinging?

 

hmmmm. has this problem persisted on only one tank of gas, or on multiple?

 

many tanks, seems the pinging has vanished, it drives ok, i replaced the small o-ring gaskings on the plenum, also cleaned the egr pipe, it was blocked closed.replaced pcv valve and seal also.

 

Now that you changed the gaskets, I would make the ECU go totally dumb and make the car relearn how you drive. This may claer up the sloppyness.

The ECU might have been compensating for a long time and now it doesn't know what to do with a solid system.

And I would put the PCV valve back in to make sure all the ventilations are correct. Sometimes these computers can be pretty picky.

 

Ok heres the verdict, i had one of the Evap solonoid purge lines backwords and the ecu had to relearn, today after 25 miles of driving she purrs now, it has the throw you back in the seat acceleration again, it seems to be going good, very little ping now, iam gona fill up with shell 93 and drive to pittsburgh tommorow, that should clean her out.

 

How was it blocked? Just full of el crapola?

You only replaced gaskets beyond cleaning the EGR?

 

thats basicly it and installed a missing pcv valve.
i went my friends garage, i cleared the codes and it seems like i did all that work for nothing, the pinging is back and its as if nothing changed........................................... ...............

 

It also sounds like it could be a timing issue.

 

Glad you figured it out professor.

 

Nope it came back after 25 miles.

 

I am almost thinking this is part of it. You fixed stuff. Ran like crap. You found your mistake and it ran "better". Part of running better was resetting the ECU. I personally dont know how long it takes an ECU to learn, but 25 miles seems "about" right for a good partial learning.

You mentioned you hooked up the car to a data logger and the streaming data looked "ok". Given the scenario you just went through, I would do another reset to see if the pinging goes away for a while. Did it come back instantly or slowly or..? Just seems you had the "best" result tied to an ECU reset versus all the mechanical work you did.

I am curious if the ECU is being fed a bad parameter and ADVANCING instead of retarding your timing and causing serious knock. However, given that thought, I would have thought that somewhere a table would be out of balance and throw a CEL/MIL.

Is the knock sensor the only input for retarding/advancing timing by the ECU?

 

The ECM controls/varies the ignition timing using the inputs from the MAF, TPS, camshaft pos. sensor (phase), both crank pos. sensors, vehicle speed, and coolant temp. If the ECM gets an appropriate knock "signal" from the knock sensor it will retard the timing to eliminate the knocking, but it normally is not required/used if the basic ignition timing is correct and everything is working as it should. Professor.......what is the ignition timing at idle? I do not understand why you would have ever removed the PCV valve and how exactly did you do it? The breather/blowby vapors were going where?......atmosphere or into the intake only via the crankcase vent/blowby hose?? The PCV system IS part of the emissions control and fuel delivery system on these cars and the crankcase has to be basically......"tight"......or a closed system. What intake do you have on this car?

 

Ugh. Im in for a fix.

Bad gas- nope
Timing-
ECU-
Gasket not sealed correctly-

 

I know of my FI car, I have a PVC with a breather element on it. I dont pump it into the intake for reburn as to keep it "cleaner". Professor seems to have capped it off totally prior the mechanical work and then replaced the seals and reinstalled it.

 

Any update on drivablity or additional work on your problem?

 

I seem to have a similar problem.

I just replaced the MAF sensor today. The car still does the exact same thing.

The car starts and runs fine at times and then it will idle low and stall.

When the car idles and runs correctly the timing is around 15 btdc which is in spec. At times when warm, I give it some gas and then let it try to idle at goes really low and the timing goes to 23 to 30 btdc.

And even when I have the throttle open so the car is at 800 rpm the timing is at 25 BTDC.

So what is causing the timing to over advance, Cam or crank sensors?????????

 

Well Today i checked all the sensors and i found that the knock sensor is bad, i dont know if this will remedy the problem, ill be replacing it in about 4 weeks time, there not cheap...... i can get it at cost where i work under $100 so once i replace that and if it still pings iam going to lose my mind.

 

the pcv has been replaced with new oem, it was remove due to a bad pcv valve grommet in the past

 

so up to date, everything is back to oem, i did install new plugs, along with the intake gaskets, but as i mentioned earlier, the knock sensor tested bad.

 

Here is to hoping its the knock sensor!

 

well i got bad news, its not.

 

So i believe i found the problem after countless hours of stress and research online, It appears my purge control valve is faulty, it is letting to much pressure build up in the fuel tank and iam assuming its forcing air into the fuel rails, I also think the boost sensor/map sensor up front is what monitors the pressure and when it reaches a limit it sends a signal to the purge valve to open and release the pressure, thats my theory because for some reason All Data calls the boost sensor a fuel pressure monitor, i dont know if this is true or not however i did a simple test, I opened the fuel cap and let it loose, closed the cover and drove home in 90+ degree weather and i did not have ANY pinging at all, so the issue seems to lay in that fuel tank pressure sensor or the purge valve. This is the first thing that ive gained results with, everything else ive tried gave me 0 results.

 

None of the above, i unhooked the battery, left it sit like 6 hours, hooked it up, car would barely run or idle, no power, backfiring thru the intake, it was bad, limped it home and ordered a new MAF, let the battery unhooked for 8 hours, installed MAF, fired right up, purrs good, drove it, feels like a new motor, no pinging or hesitation, so far so good, iam going for a ride now and gona hit some steep grades and see if it pings, if not i beleive it was the MAF the whole time.