So, all of a sudden my idle goes belly up...It's stumbled on occasion, maybe once a day but I only noticed it when at a stop.

Well tonight on my way home from work, I notice that the wagon is shaking and the engine is idling around 500rpms. There's no power, feels like it's running on 4 cylinders. I notice a egg smell as well. Yes I know, classic signs of clogged cat. But wait there's more!

I limp home and it finally just stalls out a block away. I start it up and takes a few seconds longer than usual. I put it in D and it coasts into my driveway. If i give it any kind of gas, it dies. I decide to check to see if maybe I ripped a new silicone hose off, or maybe the idle air hose is split.

IC hoses look normal, no blown off or split vacuum lines. I take off plug cover and inspect all of the plugs. Cylinder one through three plugs look normal, if not a little on the lean side. Cylinder four plug looks soaked in gas, five looks like the first three. I take off the cap and wires. These were new when I purchased the car two months ago. I try and measure resistance in all of the wires, but I'm not getting anything in any of the wires. Is this normal? Not even continuity.

I reseated all plug wires, reinstalled everything and started it up. It was rough for about one minute then it smoothed out like usual. Then a few minutes later it started stumbling again. Slight egg smell out of the tail pipe and felt like a few weak exhaust stream and a little more loppy than usual.


So, I'm either my plug wire(s) went **** up, cam sensor, fuel pump, or possibly plugged cat.

Mods are nothing more than silicone hoses, ARD ECU and AEM cone filter fronted on the MAF.

Recent engine work includes PCV system service. I haven't pulled the timing cover yet to see if maybe the timing jumped.

Also, there is NO CEL.

Any thoughts from anyone?

 

 

Nobody else have any possible suggestions?

 

What are the fault codes when you run a scan? Check the intercooler, if this is cracked or is broken it can make them run aweful (assuming yours is a turbo).
Good Luck

 

Plumbing is tight, no codes either. I'm shot-gunning all the ignition components, except for the coil, as the coil is good.

cap, rotor, iridiums, wires.

 

After replacing ignition parts, getting blues installed, retuning the ARD ECU, it's still doing it, but only after the engine is fully warmed up.

Had to jump the car today, took it for a drive for about 5-10 minutes and it drove great. Then the idle started dropping, getting rough, etc. Drove it home and then the car died. It wouldn't start back up. Lots of clicking and no battery power.

Battery is on the charger right now. I'm wondering if my alternator is on it's way out. Going to stick a multimeter to it in a little while.

 

Cleaned IAC, it was a little gummed up, but still doing the same bull**** after fully warmed up. Maybe changing out the coolant sensor? Don't know why I would do that, because it's reporting correct numbers in torque and live data. When the stumbling starts, the O2 voltage jumps up to .600 and over .830v System is in closed loop mode as well. Something is causing it to jump into stupid mode and dump fuel.

Does no one seriously have no other suggestions?

 

I'm going to guess that you're dealing with a 98 model since you have plug wires. What you are describing sounds more like an upstream oxygen sensor issue.

 

You think it could be? It's a new sensor and seems to be reading fine. No CEL.

 

Checked timing on it, dead nuts on. Cam sensor is fine, crank sensor is fine, TB cleaned.

Going to go back to fuel pressure or exhaust. Going to unhook the downpipe and see if things improve. If not, settling on fuel.

What is static pressure at idle supposed to be? 43.5psi if optimum? what should happen if I remove the vacuum line to the FPR? Should fuel pressure rise or fall?

One thing I haven't done is check compression...I'll do that as well.

 

It's been raining so no working on it yet. Hopefully this weekend.

Can anyone answer my question about fuel pressure? I search and get various answers. Just want something solid.

Thanks

 

Popped off the exhaust, still running like a pig rich a-hole. Smoking like crazy, no sulfur smell.

Could it really just be bad gas?

Anyone? Bueller?

 

How old is the gas ??

When you pull the vac line off the fuel pressure regulator the pressure should increase a bit. It should also be bone dry on the end of the FPRs nipple and not smell of raw gas.
If it's ruptured the engine can suck raw fuel through that vac line and make the engine rich and that would cause a sulfur smell from the extra gas the cat can't handle.

 

Filled tank in november, and a after about a half tank it started acting like this. When I last checked fuel pressure it was dry and I don't recall if there was a fuel smell coming from it. I also don't remember if I noticed any movement of fuel pressure up/down when I did remove it. I may have done that after I shut off the engine.

I will test fuel pressure again this week after I do a compression check. I misplaced my plug socket.

Also, what's the static fuel pressure supposed to be? 38-43psi? I've read that it is supposed to jump up to 10psi when you blip the throttle, then settle back down. True?

 

Pulled compression today (cold, WOT).

180
185
185
125
185

Other than a burnt valve...could it be a stuck/bound up valve? There's no strange tapping or anything going on in the top of the motor.

At least I can stop chasing my tail.

 

Rats.