starting issues

[sphippler]

i have an 88, 4wd, xe. it runs very rough upon starting. it usually starts right up and runs very rough for about 3-5 seconds and then smoothes right out. it also runs at a high rpm. when its cold it'll run about 1300-1900 rpm, when it warms up it's about 800-1200rpm. ive noticed the idle also pulses a little (50 rpm). once the engine runs for a few seconds it actually runs very smooth and does not stall or hesitate or have a lack of power or anything like that. all of these problem started in the last few months.

 

a while back it had another issue for about a week and then it went away (i dont know if its related). the issue was that it would start right up and then die within about a second when it was cold (once the engine was warm it did not do this). it would not even try to start up after that. it would crank and crank like it wasnt getting any spark. i finally discovered that if i held the gas pedal to the floor and cranked it over for about 15 seconds it would start to fire and then start. once it did start it would puff out a giant cloud of white smoke and smell like gas. so i dont know if the engine flooded and caused the starting problem or if the cloud was a result of me holding the pedal down. either way this problem lasted about a week and went away.

 

i have checked all the vaccume lines.

the plugs, cap, rotor, and fuel filter have been recently replaced.

the tin foil tube going from the exaust manifold to the air cleaner housing is connected.

the choke "appears" to be functioning corrrectly.

i ran a can of seafoam down the brake booster vaccume line

added fuel system cleaner to gas tank

i havnt checked for codes

 

im about to the point of just taking it somewhere and paying a bunch of money for them to diagnose it. if any one has any ideas let me know.

[1994SEV6]

i have an 88, 4wd, xe. it runs very rough upon starting. it usually starts right up and runs very rough for about 3-5 seconds and then smoothes right out. it also runs at a high rpm. when its cold it'll run about 1300-1900 rpm, when it warms up it's about 800-1200rpm. ive noticed the idle also pulses a little (50 rpm). once the engine runs for a few seconds it actually runs very smooth and does not stall or hesitate or have a lack of power or anything like that. all of these problem started in the last few months.

 

a while back it had another issue for about a week and then it went away (i dont know if its related). the issue was that it would start right up and then die within about a second when it was cold (once the engine was warm it did not do this). it would not even try to start up after that. it would crank and crank like it wasnt getting any spark. i finally discovered that if i held the gas pedal to the floor and cranked it over for about 15 seconds it would start to fire and then start. once it did start it would puff out a giant cloud of white smoke and smell like gas. so i dont know if the engine flooded and caused the starting problem or if the cloud was a result of me holding the pedal down. either way this problem lasted about a week and went away.

 

i have checked all the vaccume lines.

the plugs, cap, rotor, and fuel filter have been recently replaced.

the tin foil tube going from the exaust manifold to the air cleaner housing is connected.

the choke "appears" to be functioning corrrectly.

i ran a can of seafoam down the brake booster vaccume line

added fuel system cleaner to gas tank

i havnt checked for codes

 

im about to the point of just taking it somewhere and paying a bunch of money for them to diagnose it. if any one has any ideas let me know.

 

If you have the Z24 then I would check the carb.

 

Hmm..sounds weird. All the stuff I was thinking about while reading your post you said you did.. I would have strongly recommended the vacuum lines. check them again. they make your engine do crazy things.

 

I'm reading through the things you did. you say "tin foil tube going from exhaust manifold to the air cleaner housing in connected"? That sounds like a EGR thing, but I have no idea what you're talking about. You MUST have a Z24.

[Kingman]

The tin foil thing is the hot air pickup to aid in warming the engine. Almost all carbureted/TBI engines have them.

 

Do check for codes, that's always the first thing to do.

[Kingman]

Also, the reason why the engine would start with your foot to the floor is because that activates a cool feature that shuts down the fuel injectors so you CAN start the engine in case it got flooded.

[1994SEV6]

The tin foil thing is the hot air pickup to aid in warming the engine. Almost all carbureted/TBI engines have them.

 

Do check for codes, that's always the first thing to do.

 

Does the VG30E have that hot air pickup? My exhaust pipes don't have any sort of tubes or anything like that

[Slartibartfast]

My 95 kept stalling after starting/at low RPM, and apparently it was something with the plug for the throttle position sensor. Then again, sounds like you've got a different engine.

[sewebster]

Does the VG30E have that hot air pickup? My exhaust pipes don't have any sort of tubes or anything like that

 

No, it is no carburated or TBI.

[1994SEV6]

No, it is no carburated or TBI.

 

TBI? throttle body injection?

[Trogdor636]

TBI? throttle body injection?

 

Yes.

[1994SEV6]

Yes.

Do I not have a throttle body?

[Trogdor636]

You have multi port fuel injection. MPFI. You have a throttle body, however your injectors are not in the throttle body.

Edited November 26, 2011 by Trogdor636

[nunya]

Keep it on topic... If you want to learn about YOUR motor, please refrain from doing it in a thread for someone with an issue with different one has... The litte 'i' makes a difference compared to the 'e' at the end of the engine code... research can be a good thing over assuming.

 

OP, start with a code check, it's free and simple (I'd search the write up for you but I don't like the mobile search function. Think it's pinned in the how to section though). That will give you a starting point. You say you did tune up related stuff, are the plugs gapped correctly? Did you play with timing at all or even check it? You unplug anything and possibly forget to plug it back in? Do a slow retrace of your steps of when you did the work, double checking everything 'just' to make sure.

[1994SEV6]

Keep it on topic... If you want to learn about YOUR motor, please refrain from doing it in a thread for someone with an issue with different one has... The litte 'i' makes a difference compared to the 'e' at the end of the engine code... research can be a good thing over assuming.

 

OP, start with a code check, it's free and simple (I'd search the write up for you but I don't like the mobile search function. Think it's pinned in the how to section though). That will give you a starting point. You say you did tune up related stuff, are the plugs gapped correctly? Did you play with timing at all or even check it? You unplug anything and possibly forget to plug it back in? Do a slow retrace of your steps of when you did the work, double checking everything 'just' to make sure.

^^^

Pretty much the best thing to do in your situation I think. Like Nunya said, something could be installed incorrectly

[ahardb0dy]

I would check the codes first, also I would check and clean the butterfly in the throttle body, the TB is designed so that when the butterfly is fully closed a small amount of air can still get thru which allows the engine to idle, over time the edges of the butterfly get a build up on it and this can reduce the opening so air has a hard time getting thru and can cause the idle to be rough. If you have the V6 I would also check the thermo element( which contains a wax element inside) that controls the position of the butterfly, basically it raises the idle when cold until the coolant that flows thru it heats up causing the wax to melt and this allows the idle to drop to the normal range. There is a procedure in the FSM for measuring the amount of stroke in the rod that pushes on the cam on the TB linkage, the rod comes out of the thermo element housing. But checking the codes would always be the first step.

 

Sorry not sure if the 4 cylinder has the thermo element, I am only familiar with the V6

Edited November 26, 2011 by ahardb0dy

[1994SEV6]

I would check the codes first, also I would check and clean the butterfly in the throttle body, the TB is designed so that when the butterfly is fully closed a small amount of air can still get thru which allows the engine to idle, over time the edges of the butterfly get a build up on it and this can reduce the opening so air has a hard time getting thru and can cause the idle to be rough. If you have the V6 I would also check the thermo element( which contains a wax element inside) that controls the position of the butterfly, basically it raises the idle when cold until the coolant that flows thru it heats up causing the wax to melt and this allows the idle to drop to the normal range. There is a procedure in the FSM for measuring the amount of stroke in the rod that pushes on the cam on the TB linkage, the rod comes out of the thermo element housing. But checking the codes would always be the first step.

 

Sorry not sure if the 4 cylinder has the thermo element, I am only familiar with the V6

wow. THAT is cool.

[sphippler]

YOU GUYS WERE TALKING ABOUT MAYBE I UNPLUGGED SOMETHING OR INSTALLED SOMETHING WRONG BUT THIS ISSUE DIDNT START RIGHT AFTER ANY REPAIRS. IT WAS MONTHS AFTER ALL OF THAT.

 

ANOTHER ISSUE THAT MAY BE RELATED IS THAT THE ENGINE IS DEVELOPING OIL LEAKS (I KNOW IT SOUNDS REDICULOUS). ABOUT THE SAME TIME AS IT HAD ITS NONSTARTING ISSUES, IT DEVELOPED AN OIL LEAK THROUGH THE OIL PRESSURE SENSOR. I REPLACED IT AND IT QUIT LEAKING. THE VERY NEXT DAY IT STARTED LEAKING OIL FROM THE FRONT MAIN SEAL. THIS SEEMED LIKE A STRANGE COINCIDENCE SO I THOUGHT IT MIGHT BE DUE TO A CLOGGED PCV VALVE. I REPLACED IT BUT IT DIDNT HELP. I DID HOWEVER DRIVE AROUND WITH THE OIL FILLER CAP OFF FOR A WHILE TO SEE IF I WAS GETTING PRESSURE BUILD UP IN THE CRANK CASE. IT SEEMED TO HELP THE OIL LEAK. MAYBE IT IS GETTING SOME BLOW BY FROM A CYLINDER OR MAYBE THE TWO OIL LEAKS WERE A COINCIDENCE. I HAVNT FIXED THE FRONT MAIN SEAL YET SO I DONT KNOW IF THERE WILL BE A THIRD LEAK.

 

IVE NOTICED WHEN I FIRST START IT AND ITS RUNNING POORLY THAT IS HAS A VERY LOUD CLATTERING NOISE (SOUNDS LIKE ALL OF THE LIFTERS ARE CLATTERING DUE TO NO OIL PRESSURE)FOR A FEW SECONDS. IM NOT ALL THAT FIRMILIAR WITH OVER HEAD CAM ENGINES (IVE DEALT MOSTLY WITH OLD CHEVYS AND JEEPS) SO I DONT EVEN KNOW IF IT HAS ANY TYPE OF LIFTER OR ROCKER ARM. SO MAYBE IT IS LOOSING OIL PRESSURE OVERNIGHT (POSSIBLY DUE TO THE OIL LEAK) AND THEN WHEN I START IT THE DEFLATED LIFTERS ARE CAUSING IT TO RUN POORLY UNTIL THEY FILL BACK UP WITH OIL. HOWEVER THIS DOES NOT EXPLAIN THE HIGH IDLE.

 

IM GOING TO GO OVER THE VACCUME LINES AGAIN THIS WEEKEND AND LOOK AT THE THROTTLE LINKAGE. ILL PULL A FEW OF THE PLUGS AND EXAMINE THEM. ILL TRY A VACCUME GUAGE TOO. I GUESS THEN ILL CHECK THE CODES.

Edited November 27, 2011 by sphippler

[1994SEV6]

YOU GUYS WERE TALKING ABOUT MAYBE I UNPLUGGED SOMETHING OR INSTALLED SOMETHING WRONG BUT THIS ISSUE DIDNT START RIGHT AFTER ANY REPAIRS. IT WAS MONTHS AFTER ALL OF THAT.

 

ANOTHER ISSUE THAT MAY BE RELATED IS THAT THE ENGINE IS DEVELOPING OIL LEAKS (I KNOW IT SOUNDS REDICULOUS). ABOUT THE SAME TIME AS IT HAD ITS NONSTARTING ISSUES, IT DEVELOPED AN OIL LEAK THROUGH THE OIL PRESSURE SENSOR. I REPLACED IT AND IT QUIT LEAKING. THE VERY NEXT DAY IT STARTED LEAKING OIL FROM THE FRONT MAIN SEAL. THIS SEEMED LIKE A STRANGE COINCIDENCE SO I THOUGHT IT MIGHT BE DUE TO A CLOGGED PCV VALVE. I REPLACED IT BUT IT DIDNT HELP. I DID HOWEVER DRIVE AROUND WITH THE OIL FILLER CAP OFF FOR A WHILE TO SEE IF I WAS GETTING PRESSURE BUILD UP IN THE CRANK CASE. IT SEEMED TO HELP THE OIL LEAK. MAYBE IT IS GETTING SOME BLOW BY FROM A CYLINDER OR MAYBE THE TWO OIL LEAKS WERE A COINCIDENCE. I HAVNT FIXED THE FRONT MAIN SEAL YET SO I DONT KNOW IF THERE WILL BE A THIRD LEAK.

 

IVE NOTICED WHEN I FIRST START IT AND ITS RUNNING POORLY THAT IS HAS A VERY LOUD CLATTERING NOISE (SOUNDS LIKE ALL OF THE LIFTERS ARE CLATTERING DUE TO NO OIL PRESSURE)FOR A FEW SECONDS. IM NOT ALL THAT FIRMILIAR WITH OVER HEAD CAM ENGINES (IVE DEALT MOSTLY WITH OLD CHEVYS AND JEEPS) SO I DONT EVEN KNOW IF IT HAS ANY TYPE OF LIFTER OR ROCKER ARM. SO MAYBE IT IS LOOSING OIL PRESSURE OVERNIGHT (POSSIBLY DUE TO THE OIL LEAK) AND THEN WHEN I START IT THE DEFLATED LIFTERS ARE CAUSING IT TO RUN POORLY UNTIL THEY FILL BACK UP WITH OIL. HOWEVER THIS DOES NOT EXPLAIN THE HIGH IDLE.

 

IM GOING TO GO OVER THE VACCUME LINES AGAIN THIS WEEKEND AND LOOK AT THE THROTTLE LINKAGE. ILL PULL A FEW OF THE PLUGS AND EXAMINE THEM. ILL TRY A VACCUME GUAGE TOO. I GUESS THEN ILL CHECK THE CODES.

 

If you want anyone to read that, I suggest you retype it in regular lowercase letters.

But then again, if you didn't want help, then this is the way to go

 

BUT SERIOUSLY THOUGH. I READ ALL OF IT, AND HERE'S WHAT I THINK. I can't do this. Seriously. It hurts my eyes. I was trying to give you a taste of your own medicine but it hurts too much to type like that.

 

Anyway, I think you were trying to say that there is too much oil pressure. You were trying to hint that every time you plug a hole, a new leak pops up. You said you fixed a leak, and then it leaked somewhere else.

To actually help you, I think you need to understand a few things. These are overhead engines, like you said. They do have rocker arms and lifters. Lifters do need oil. I don't know what you mean by "inflated", but clattering on start-up is usually lifters. This is usually to a clog in the oil system, low quality/bad oil, or a bad oil filter.

Now you said "loosing oil pressure overnight", are you sure you know how an engine works? When the engine runs, it powers an oil pump which pumps oil where it needs to go and creates pressure. That oil pump doesn't work when the engine is off. The engine looses oil pressure the instant the engine is off, it doesn't take over night.

Yes, you need oil on lifters during start up. That's why you buy a high quality oil that stays lathered on the lifters. High quality oils STAY coated on the surface to prevent wear on start up.

[sewebster]

If you want anyone to read that, I suggest you retype it in regular lowercase letters.

But then again, if you didn't want help, then this is the way to go

 

BUT SERIOUSLY THOUGH. I READ ALL OF IT, AND HERE'S WHAT I THINK. I can't do this. Seriously. It hurts my eyes. I was trying to give you a taste of your own medicine but it hurts too much to type like that.

 

Anyway, I think you were trying to say that there is too much oil pressure. You were trying to hint that every time you plug a hole, a new leak pops up. You said you fixed a leak, and then it leaked somewhere else.

To actually help you, I think you need to understand a few things. These are overhead engines, like you said. They do have rocker arms and lifters. Lifters do need oil. I don't know what you mean by "inflated", but clattering on start-up is usually lifters. This is usually to a clog in the oil system, low quality/bad oil, or a bad oil filter.

Now you said "loosing oil pressure overnight", are you sure you know how an engine works? When the engine runs, it powers an oil pump which pumps oil where it needs to go and creates pressure. That oil pump doesn't work when the engine is off. The engine looses oil pressure the instant the engine is off, it doesn't take over night.

Yes, you need oil on lifters during start up. That's why you buy a high quality oil that stays lathered on the lifters. High quality oils STAY coated on the surface to prevent wear on start up.

 

The lifters have oil inside. Ideally it stays there, because if it leaks out then the lifters get shorter and make the clackety-clack sound. Fortunately they get "re-inflated" by oil pressure when the engine is running, so it usually only happens on startup if the oil got out. This is why you are supposed to always store lifters upright when you take them out. The point of the hydraulic lifters is that they automatically adjust the valve lash. But I'm not really sure it's worth it sometimes... might be just easier to adjust it manually. I think manufacturers have gone back to manual lash adjustment actually, but probably just to save money.

[1994SEV6]

The lifters have oil inside. Ideally it stays there, because if it leaks out then the lifters get shorter and make the clackety-clack sound. Fortunately they get "re-inflated" by oil pressure when the engine is running, so it usually only happens on startup if the oil got out. This is why you are supposed to always store lifters upright when you take them out. The point of the hydraulic lifters is that they automatically adjust the valve lash. But I'm not really sure it's worth it sometimes... might be just easier to adjust it manually. I think manufacturers have gone back to manual lash adjustment actually, but probably just to save money.

Yeah. that makes sense. Lifters seem to give people a lot of problems. I only know anything about the vg30e. I'm pretty much clueless on any other type of engine. What is there besides OHV? What type of engine doesn't have overhead valves? A boxer maybe?

[JamesRich]

The lifters are what is causing the ruff running for the first few seconds when you start it. When they collapse they don't open the valves as far as needed. With some collapsed and some still pumped up your engine is running off balance till they all pump up. My 87 does this sometime and other times it doesn't. From what I've read searching its kind of common so I just ignore it. Now if they continue to click for a while after its running then you might look into changing them but they aren't cheep.

The high idle is probably a vacuum leak. Check the hoses under the air cleaner and there is a vacuum tree behind the throttle body. Also check all the pollution crap on the fender on the drivers side, I had a leak there too.

James

[sphippler]

thank you for the all the advise. i still havn't figured out the problems though. i guess my most important question is; what would cause pressure in the crank case. first the oil pressure sensor started leaking, i replaced it. two days later the front main seal started leaking. this could be a coincidence and there may not be a crank case pressure problem. ive also replaced the pcv valve. the engine runs very smooth a few seconds after starting so i dont think there is a blown head gasket or cracked block or head. on a side note, ive debated connecting a vaccume hose to the crank case vent tube on the tappet cover to give a little more vaccume to the crank case, at the very least i dont think it will cause any problems ( well maybe it could cause a small amout of increased oil consumption.

any thoughts, let me know.