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Re: temp guage reading and pinging, oil pressure spikes?

Posted: March 22nd, 2009, 4:00 pm
by crustodd
Oh Yeah,
When I'd be cruising at a constant 70-75 or whatever, if I let of the throttle all the way, it'd kinda' "buck". A herky-Jerky sensation, like when you go on/off the gas in a manual trans rig. If I let off the throttle easy and kept VERY light pressure on the pedal it didn't do it or it was almost unnoticeable. It seemed worse at higher speeds.

Re: temp guage reading and pinging, oil pressure spikes?

Posted: March 22nd, 2009, 4:20 pm
by Mgardiner1
Are you familiar with testing resistance with a digital multi-meter? See if you can google what the resistance of the various sensors are supposed to be. Sounds like a coolant temp or air intake temp sensor may be reading incorrectly for you.

Re: temp guage reading and pinging, oil pressure spikes?

Posted: March 22nd, 2009, 4:25 pm
by crustodd
Hey Mike? Is that your first name?
How would those sensors create such an odd response if they were malfunctioning?

Re: temp guage reading and pinging, oil pressure spikes?

Posted: March 22nd, 2009, 4:31 pm
by crustodd
Oh yeah,
The oil pressure thing appears to be the sending unit. Easy fix.

Re: temp Gage reading and pinging, oil pressure spikes?

Posted: March 22nd, 2009, 6:18 pm
by jsawduste
Todd,
sounds like the IAC (located behind the TPS on the throttle body) is acting up. Before doing another TPS I would check the IAC, clean out the air passages in the TB before installing a new one. Check for a vacuum leak also.

Ping and detonation are two different things. You might try the higher octane to see if it helps. Ping is "generally" caused by a lean A/F mix. Exacerbated by a high compression ratio. Detonation is the flame front traveling to fast. Which is "normally" caused by the quench being less the optimum. Which in a stroker is around .042. Or to high of a compression ratio for the fuel octane.

As always YMMV.

Adjustable MAP sensors are only effective on WOT.

Re: temp guage reading and pinging, oil pressure spikes?

Posted: March 22nd, 2009, 6:23 pm
by SilverXJ
I understand completely about the sounds. In my experience sounds that you aren't familiar with lead to failure. I know first hand. That does sound like a TPS... when I put my first stroker in it did what you described. It was also verified by my Apexi which can display the throttle position.

-Chris

Re: temp guage reading and pinging, oil pressure spikes?

Posted: March 22nd, 2009, 7:30 pm
by crustodd
Here's an update,
I got down to about 1/8th of a tank after my freeway jaunt today. I thought this'd be a good time to add some 110 octane Sunoco to see what it'd do. I put in around 2 1/2-3 gallons to the gas I still had in the tank. PRESTO...no ping! FIERCE acceleration! I filled it up the rest of the way after I did a few WOT blasts and we'll see how that works. The ping was pretty light to begin with and hopefully it's a fine-tune issue. jsawduste-Is the IAC the other sensor that bolts to the T-Body on the valve cover side? What's it's function?

Todd

Re: temp guage reading and pinging, oil pressure spikes?

Posted: March 22nd, 2009, 10:41 pm
by jsawduste
crustodd wrote:Here's an update,
I got down to about 1/8th of a tank after my freeway jaunt today. I thought this'd be a good time to add some 110 octane Sunoco to see what it'd do. I put in around 2 1/2-3 gallons to the gas I still had in the tank. PRESTO...no ping! FIERCE acceleration! I filled it up the rest of the way after I did a few WOT blasts and we'll see how that works. The ping was pretty light to begin with and hopefully it's a fine-tune issue. jsawduste-Is the IAC the other sensor that bolts to the T-Body on the valve cover side? Yes it is What's it's function? Idle Air Control. Controls the amount of air the TB gets at idle. Can cause the symtoms you are having. I would however check all the vacuum lines and ports for a leak first.
Todd

Re: temp guage reading and pinging, oil pressure spikes?

Posted: March 28th, 2009, 9:14 pm
by crustodd
UPDATE--

Okay, I did a few things and here's where I'm at. Replaced the T-Stat, engine now runs around 210 at a standstill and cools to 180-190 in motion. Checked AIC, it's good. Replaced O2 sensor, it was a bit slow in its response. Checked fuel pressure, 39 psi. Is this about right with the Hesco FPR and the '99-up intake? I'm running the Ford #24 lb. injectors. Relocated the IAT to the AEM air filter, which has a hole to allow this.
NOW...it's not pinging', but it acts like it's running out of ignition timing or fuel around 4600-4800. If I'm in neutral or park it revs right up to 5-6K, whatever. Under a load and in motion, it runs out of "power" and starts to crap out at the above mentioned rpms. It seems to be happening for no particular reason. It wasn't doin' this a few days ago. :huh:

T

Re: temp guage reading and pinging, oil pressure spikes?

Posted: March 28th, 2009, 9:59 pm
by jsawduste
crustodd wrote:UPDATE--

Okay, I did a few things and here's where I'm at. Replaced the T-Stat, engine now runs around 210 at a standstill and cools to 180-190 in motion. Checked AIC, it's good. Replaced O2 sensor, it was a bit slow in its response. Checked fuel pressure, 39 psi. Is this about right with the Hesco FPR and the '99-up intake? I'm running the Ford #24 lb. injectors. Relocated the IAT to the AEM air filter, which has a hole to allow this.
NOW...it's not pinging', but it acts like it's running out of ignition timing or fuel around 4600-4800. If I'm in neutral or park it revs right up to 5-6K, whatever. Under a load and in motion, it runs out of "power" and starts to crap out at the above mentioned rpms. It seems to be happening for no particular reason. It wasn't doin' this a few days ago. :huh:

T
Are you sure this is the correct RPM ? Is it acting like it is bouncing off the rev limiter ? Sounds like it.

Mine spins up to 5200 with 24 lbers and 39 pounds no problem.

Reason I ask is that a buddy of mine had an aftermarket tach and had it set to read an 8 cylinder engine. Thus it was was always reading "slow".

Re: temp guage reading and pinging, oil pressure spikes?

Posted: March 28th, 2009, 10:03 pm
by crustodd
Hey Jsaw,
Yeah that's almost what I thought it was, but it "feels" like it's running out of steam too. Before it started to do this, it'd run through the revs and if it was, say, on wet pavement, it'd spin the tires right through the revs and then bounce off the rev limiter. Now it seems like it's chocked off when it gets up around 4600-5000. I don't even think it'll rev up to the limiter under load right now. Odd.

T~

Re: temp guage reading and pinging, oil pressure spikes?

Posted: March 28th, 2009, 10:06 pm
by crustodd
I realized, I just changed the plugs to two rages cooler last week. I wonder if that plus the cooler operating temp is causing issues? I have the plugs gapped to .045. Too much?

Re: temp guage reading and pinging, oil pressure spikes?

Posted: March 28th, 2009, 10:10 pm
by jsawduste
crustodd wrote:I realized, I just changed the plugs to two rages cooler last week. I wonder if that plus the cooler operating temp is causing issues? I have the plugs gapped to .045. Too much?
Put the warmer plugs back in a take it for a spin. You really should not need the colder ones. .045 might be a bit much if the ignition is a bit weak. Betcha they are black and sooty from not getting hot enough.

Let us know how it works out.

Re: temp guage reading and pinging, oil pressure spikes?

Posted: March 28th, 2009, 10:44 pm
by crustodd
Hey J,
Well, when I took the Champion 12rc's? out, they had a MEAN blast of fused on splatter on the side that was gettin the combustion burst! I suspect it was the oil gettin' by the rings before they were better seated and then combined with the slight pingin'... Looked a bit scary though :shock: I have the MSD al6 brain, blaster off-road coil, and the fatty 8.5, I think, wires. It should be PLENTY strong enough. I may try then to see if there's an improvement though.

Thanks,
T~