BowTied

Glad to hear it is fixed. Keep an eye on your coolant, it may need another flush soon if the system was that gummed up before. Good luck.

WTF? A shop just did a flush and they missed the rad was plugged? They are hosing you, big time. This flsuh should be free!!!!!!

Ouch, sory about the luck there. That might be worth a new topic of nothing comes up in the search....

Oh it was sudden, they I tend to agreewith electrical. Coil comes to mind first, though I would have thought it would fail outright, bad ground strap rotted/fell off somewhere? Were you doing any work under the hood just prior? Perhaps the distributor got bumped and timing is retarded. DId this start before or after the tune-up? If after, double check your firing order and timing.

Hmm, not getting enough fuel? Plugged/bad injector? Not sure. Any codes?

You may have installed the dist off one tooth also.

It could be wet ignition components, dist cap, coil, wires. Could be several things, but that seems most likey...

It sounds a bit like the stat is not opening all the way when it needs to. I agree, flsuh rad / new hoses, stat, and rad cap if older. I presume you are running a stock fan and fan shroud, and correct grade of engine oil, and there are no check engine codes. If the temp is climbing at freeway speeds after a flush and new stat, I would wonder if the fan clutch is not operating properly and creating an air flow restriction at higher speeds (guess).

Dist cap and spark plug wires (esp if they are older, they could soak some water). Very god chance that if you leave it over night it will be fine in the morning. If you can't wait, some water displacement spray (ie WD40) should help, just don't get it all over the place (flammable)

Most engines will eventually burp the air if the rad cap is left a bit loose. Just don't leave it like that for long, the cap closed allows the system to pressurize which increases the boiling point of the coolant to prevent overheating. On a cooler day, it should nto be a big deal to run it in your driveway like this for 10-15 minutes, just keep an eye on it. The shop may? have dumped the extra from a bottle in the overflow. If you have a way to take some out go ahead, but that being over full should not alone cause any problems (maybe the overflow would overflow, lol). Take it to a shop that as an temperature gun that can detect the temperature on the surface of the stat housing, maybe that will tell the tale of the actual temperature. I trust you are running stock fan and stock shroud, these are important items.

Gents, I have read this thread and have some things for consideration... A thermostat is not a digital device that is on or off. It opens gradually. It will open and close as it needs to in order to regulate the temperature to its setting. It will eventually find the spot that restricts just enough flow to maintain the temperature of the coolant. The temperature of the stat and the actual temperature of the engine and the reading on the gauge are subjects to a few things. The stat has a manufacturing tolerance that maybe give it 5 degress of variance in my estimation. The guage may have a similar calibration concern. Also, the gauge source (where the gauge takes the reading on the engine) may not be the same temperature as the coolant at the stat. There could be as much as 10 degrees difference between the coolant at the stat and the coolant in a water jacket...depending on the engine in question. So bottom line, don't sweat 175/180, it'll be close enough. Now 160 vs 190 is another story. Follow the FSM, always until that doesn't work for you. If you live in a super hot or cold climate, then you can modify slightly to suit. 90% of us should use the factory one. There could be some difference from one car to another on where a stock temp gauge that is not graduated with numbers should indicate temperature. It is my experience that 1/3 to 1/2 is tpyical. 3/4 is not typical. That doesn't mean it is out of the operating range specified by the engineers. It would however be enough for me to get a temp gun or gauge and verify what I have got. This verifies if the gauge is out of calibration or indicates if there is something else going on (trapped air, wrong/mal-function stat whatever). If it feels notably different to the owner, then that is always a good reason to get a second opinion from a professional. If you had cooling system service and asked for the same stat as before and the gauge reads way different, then something changed.... Open/Closed Loop. The stat will remain closed until the coolant reaches the temp that opens the stat. On most vehicles I have owned, this is not directly connected to the temperature setting that changes the computer from open loop to closed loop (open loop is a warm up mode that by-passes O2 sensors readings, closed loop calibrates fuel trim with the O2 sensor input data). I am not certain what the temp setting is for closed loop on this vehicle, but changing from a 175 to a 180 or 190 stat should not likley have a bearing on this (confirm with a Nissan tech) - it should not be impacted by going higher than the FSM spec'd stat. Running a much lower stat than FSM spec'd or no stat at all however would affect this as it would take a long time for the engine to reach that operating temp that triggers closed loop. No stat at all could see a cold winter driven rig never reach closed loop (sign of a stat stuck open too). One of the reasons a stat is so important. If your fan clutch is stuck on, seized, whatever, this should have no bearing on the temp. It could create unnecessary drag on the engine at times lowering fuel economy. If you added 3 additional fans to the rad, this too would not have much impact either. The stat regulates the temp. If the coolant coming in is much cooler than normal due to a stuck fan clutch, or even 3 extra fans, the stat would close and let the heat build up again and only open enough to maintain the temperature. The differences should be neglibile. Now if the cooling system was unable to maintain temp at the stat setting (such as an undersized cooling system) then extra fans could make a difference. You may already all know this, but I post it for clarity to those who may be reading along. HTH.

I thought the thread was about spark plugs. In either case, I meant leave the plugs alone until the next scheduled change interval.

I replaced my plugs when I did the power valve screws since I had it that far apart at ~110 000km. They were .044" and I recall .043" being the correct spec. As to tolerance, I could see .0015, but not .015. Modern manufacturing should not have .015 ("15 thou") for anything like this IMHO. 1.5 thou is understandable, that is less than the thickness of a peice paper. For the starting, is it turning over slower or although turning over fine just taking longer to start?

Looks good!

You are fine. 99% of the time the plugs are gapped correctly from the factory assuming you are using the correct plug. It is good practice to verify the gap before install. Once in leave till the next change interval.

The larger teh plug gap, the higher the voltage required to junp the gap meaning your coil is working harder/hotter. Follow the FSM, if still running rough, the problem could be old wires, or a host of other things.

Interesting, thanks for the reply. I wonder if this starts at a higher mileage? With just over 80k miles, I have not yet noticed any oil consumption issues yet (less than quart per oil change). I will keep an eye on it.

I had not heard this... can you elaborate? Or is this about PCV valve oil consumption? thx

I think there is a mod out there that allows you to remove the EGR, the newer 4.3s don't even have them. The 4.3 CPI need a lot of fuel pressure to run, I suspect you will need a GM fuel pump - and they are not cheap! The one on my 99 Jimmy was nearly 400 with my discount. Keep going, great thread!

Advice above is good. In an ideal world, if it is time to replace the stat, do the rad hoses, heater hoses, flush and rad cap too if not recently done. 180° is a good all around stat, you may want a 190° if you are in a cold winter climate area.

Glad you got it solved. That was a tricky one.

It does this even when you are coasting (no brakes)?

Congrats!!!!!!!!!!!!!!

Good work! You got this far, don't rush it. Now is the time to inspect things, check hoses and clamps, double check bolt torque where needed, change plugs or whatever else you want. It will never be easier than now. Double check you have all your fluids topped up before you start it. (yes, it happens!) Good luck!

glad you found it, and followed up here.