I posted this over at gm-diesel.com and they for some reason think what's in my sig is more important than my problemshttp://dieselplace.com/forum/smileys/smiley7.gif so im coming here for help as well....


I dont have a boost gauge, but I can hear the turbo... (Boost and EGT gauges will be on the way eventually)

When cold, the truck runs great, and I can hear the turbo spool up. It gets loudest at ~2400rpm, then queits down as the RPMs continue to climb. (Im assuming it looses boost at higher rpms? Is that normal too?) There is also very minimal smoking when romping it cold.

When the truck is warm, I cannot hear the turbo at all, when I romp the accellerator pedal (identicle to when cold,) the truck is sloooow and runs crazy rich, leaving a HUGE billowing black trail.

So why would I loose boost above 2400rpm when cold, and why would I loose ALL boost when hot?

thanks
Steve

ps - I JUST replaced the vacuum pump that quite literally grenaded some time ago.... All vaccum lines are intact and secured.


pps - pulled the codes and got 29 from the glow plug relay. I played with the "optional relay" under the plastic shroud on the firewall and it helps to turn on the glow plugs, but after one fire up, at the next start, the relay wont' trip the glow plugs again. Edited by: Bumpin' Yota

Engine idling, check vacuum at the turbo wg actuator,~15" and before the wg solenoid, ~25" hg.


Vacuum is used to close the wate gate and build boost pressure.

I'd bet it's the WG solenoid on the intake, if I was a betting man that is. For only 25.00 you could rule that out and this is how my was acting too.

Ok, just double checking myself, this is the waste gate actuator circled in blue right? (http://memimage.cardomain.net/member_img_a/25876_307_full.jpg)


http://memimage.cardomain.net/member_img_a/25876_307_full.jp (http://memimage.cardomain.net/member_img_a/25876_307_full.jpg) g


And this is the waste gate solenoid circled in yellow right? (This truck only has 1 solenoid, in pics of other trucks, I've seen 3?) (http://memimage.cardomain.net/member_img_a/25876_308_full.jpg)


http://memimage.cardomain.net/member_img_a/25876_308_full.jp (http://memimage.cardomain.net/member_img_a/25876_308_full.jpg) g


And 2 more questions -


1. Is there an instrument I can rent to measure the vacuum?


2. Is the waste gate actuator ONLY controlled by the vacuum and no spring assistance?


Thanks guys! :)Edited by: Bumpin' Yota

Your pictures are correct.


I mentioned your signature on gm-diesel because nobody had a clue what we were dealing with. Didn't even know for sure if it was a 6.5, though it was probably a pretty safe bet. But the best technical support people always ask the basic questions first.


Pull the vacuum tubes off the solenoid and, with the engine running, see if there's a little suction in the yellow tube by putting your finger on the end of it. If there is, then odds are your solenoid is dead. If there isn't, then your pump is dead again. But before running out and buying a new solenoid, tie the wastegate shut and go for a ride. See if the turbo spools up like it should after the truck warms up. If it does, then you know it's the solenoid.

Your pictures are correct.


I mentioned your signature on gm-diesel because nobody had a clue what we were dealing with. Didn't even know for sure if it was a 6.5, though it was probably a pretty safe bet. But the best technical support people always ask the basic questions first.


Pull the vacuum tubes off the solenoid and, with the engine running, see if there's a little suction in the yellow tube by putting your finger on the end of it. If there is, then odds are your solenoid is dead. If there isn't, then your pump is dead again. But before running out and buying a new solenoid, tie the wastegate shut and go for a ride. See if the turbo spools up like it should after the truck warms up. If it does, then you know it's the solenoid.





Thanks for the help man, I do appreciate it, and sorry about that comment, I wasn't thinking from everyone else's perspective.


Ill check that out tomorrow to see if the solenoid's action dies with heat.


BTW I just pulled out the snorkel that GM puts in the passenger side fender per recommendation of Kennedy diesel and it made a pretty good difference. 0 - 60 was ~13 seconds after doing that when cold.

Howdy Yota, welcome to the site we try to keep it civil here, but we are just plain folks and every once in a while things get "spirited" but not often and we try not to get mad. PM is a good feature you can go direct to get a better idea of what was actual meaning of a thread if unclear.


Vacuum gages are pretty inexpensive and for this truck is part of your tool kit IMO , get one that reads both vac and press up to about 15psi, go for about $20 usually found by timing lites-compression gages-diagnostic tools area, some auto-parts like auto zone have free loaner tools with a deposit. Get about 6' of rubber hose also so you can get readings in the cab while driving.


Rather than guessing about the WG sol, put a "tee" into the output of it 1 leg going to the WG and the middle leg to your gauge, 15" at idle and variable vac up to about 20-25" as PCM wants more boost it will clip some once the PCM is happy wityh boost level, if you don't see a change or only minimal change then the solenoid is probably bad, some have been revived with a shot of WD-40.


For some reason I can't get your pics up, btw using the upload button, you can direct post a pic into your message.


You may not have a problem, GM s program clips boost right about the point you are questioning, if you don't find any problems on the vac side, you will need to buy or build a boost fooler to trick the PCM into not knowing how much boost you are actually making so it won't clip fuel/boost.


Take a minute to peruse the FAQs above a lot of info in the topic links


FWIW I like to see sigs info not for bragging rights, but to better know what it is we are making recommendations on to troubleshoot.


On edit I see that I forgot to ans your WG question, yes only diphragm actuated no spring, there are spring WG actuators as aftermarket that you can build or buy that eliminates vac requirement completely, but until you reflash or rechip(in your case) you may need a fooler to keep the PCM dumb so it won't set a code or clip fuel trying to lower boost.Edited by: Turbine Doc

hmmm for some reason the pics were working when I posted, then I came back and they weren't, now after doing nothing subtaintial they are working again....odd


Thanks for the help Ill get that vacuum gauge and tubing tomorrow. (I also need to check the vacuum lines on my old 4runner...lol)





here are the two pics earlier...http://dieselplace.com/forum/uploads/BumpinYota/2004-10-21_215909_WasteGateActuator.JPGhttp://www.dieselplace.com/forum/uploads/BumpinYota/2004-10-21_220238_WasteGateSolenoid.jpg

You can check the vacuum to the "wastegate can " ( Blue circil) on the turbo by pulling that vacuum line, and or by seeing if the vacuum is holding the wastegate closed - with engine running you should have real difficulty pushing the lever to open the wategate.


also - pull, "check" and re-install the electrical connectoor on the Solenoid ( Yellow). Verify that hose vacuum lines are fully seated, too.


Boost fooler is a fairly easy mod, and worth it, but minimally should have the EGT gauge before you fool the boost.





You probably can't hear the Turbo over that 1200w sound system anyway ! http://www.dieselplace.com/forum/smileys/smiley17.gif

Stupid observation here, is that the right selonoid on there?


Mine is a green dot??

Mine has a green dot too.

It's the only solenoid I can find in the engine bay...lol (I'm red-green color blind, so I can't make out if my dot is green or yellow, what color is the dot in the pic?)


Anyhow I decided to pull the solenoid just to take a look at it...well I juuust started to play with the rubberhousing that connects the vacuum lines to the solenoid, and the yellow vacuum line coming from the vacuum pump just fell off! DOH!!


I pulled the rubberhousing and reinserted both lines solidly into that housing then reaffixed it to the solenoid.


I havent been able to get away from work today like I thought, but after discovering this at lunch it appeared to have vacuum at idle when hot. :D


I still cant believe I missed that....probably happened when the vacuum pump grenaded and was hanging by that vacuum line. (The crazy part was the diesel techs at the local stealership missed the FUBAR'ed pump...lol)

Color in the pic appears to be darn near yellow, almost close to white. Now that i look at the pic even closer, yup, looks like that plug is halfway off.

Looks like a faded out green one, 2 colors green or pink is the norm, IIRC green dot are latest generation of solenoid.

well took it for a good 10 mile run after work and when warm but not hot this thing blew my mind with how quick it took off...lol


After filling up, and heat soaking into everything, suddenly no boost, symptoms back, so I popped the hood and pulled the vacuum line going to the WG actuator - no sucky. (lol) Went back to the solenoid and tried to seat the vacuum lines better, then rechecked, still no vacuum. Pulled both lines and the rubber adapter and OMG did the yellow line have a tremendous amount of vacuum.


So it's the solenoid....


How would I use wd-40 to get it working again as someone posted? It looks like it's almost sealed save the two lines and electrical plug in.

Pull off vac lines to solenoid, and spray WD-40 into them, may or may not resurrect it, but worth an attempt.

Welp, I removed the WG solenoid valve entirely and shook it. After about 3 shakes something inside came loose.


I then sprayed it up the ying yang with wd40 into the 2 vacuum lines like you said.


Then dried it off and tried to get as much wd40 back out by lightly tapping it on a cloth.


Reinstalled it and boom, vacuum. Tomorrow we will see if this will last...


I'm going to be buying a new one ASAP, most of the autoparts stores do stock this dont they?





You probably can't hear the Turbo over that 1200w sound system anyway ! http://dieselplace.com/forum/smileys/smiley17.gif





WHAT?? I CANT HEAR YOU!! lol http://dieselplace.com/forum/smileys/hihi.gif It's more oriented towards SQ, with 600 watts on mids and highs and 600 on bass.


My 4Runner on the other hand is a competition rig with 8.8kW on bass and 0.15kW on mids and highs.


People keep telling me that there is a fine line btwn a hobby and a mental illness...lolEdited by: Bumpin' Yota

Doubtful auto parts will carry the solenoid, normally a dealer part, many will honor GM parts direct web price