Truck shaking when gas is depressed
i had this happen a couple weeks ago. when you drive it it shakes really badly when you are accelerating. i got a cylinder 7 misfire at first so i pulled the plug and made sure that it was firing..and it was...and it really wasn't that fouled out. so i changed the fuel injector and it worked for about a day then started doing it again but now it won't throw up a cel. if i turn the overdrive off it doesn't seem to shake that much either. it shakes more around 1000-2000 rpm and not so much when you get to the high rpm's. please help asap as this is my only vehicle. o yea truck is 98 1500 4x4 5.9L.
Not really fouled? what type of fouling are you talking about? Gas, coolant, oil? If the gasket on the bottom of the intake is blown (which is very common with stock gaskets) You'll be sucking oil into your cylinders and the 7 & 8 cylinders seem to be the ones that get it the most.
Sounds like it may be time for a good tune up : cap rotor plugs wires
check the rest of the ignition system and fuel pressure under a load
cap rotor and wires are new. plug is firing fine. coil is new too. the fuel pressure is correct according to the gauge that i got from auto zone. (i can't remember what the psi was lol) i also checked the compression of cylinder 7 and it was over 120 psi so that is good too. one thing that i have noticed though is that first the shrader valve in the right side of the engine (cylinders 1-7) fuel rail blew but after i replaced it it i noticed that the upper intake was wet..especially around the throttle body where it bolts at the top. and it looks wet around where i replaced the fuel injector too but i just figured that it was because that was from where when i pulled the fuel line off it sprayed everywhere...i have looked at it while running and it isn't spraying anymore... ?:( idk. one thing that i should mention...the vacuum lines for the cabin blowers (idk what they are called lol ) like heat and ac...they are busted so that all i have is defrost. I just havn't gotten around to fixing them yet lol i have been told that that effects the way it idols and such...? idk
Was the plug oily looking?
um in my opinion yes... lol i'll take a pic when i get home later today and post it. it had a real dark black ring around the bottom end of the threads and on the tip instead of being white tint or brown it was greyish black closer to black.
This TSB will help you diagnose the gasket. If it's bad, let me know and I'll post the repair procedure if you need it.
Spark Knock And Engine Oil Consumption Due To Intake Manifold Pan Gasket Oil Leak
This bulletin involves the replacement of the engine intake manifold plenum pan gasket.
1994 – 1999 (AB) Ram Van
1994 – 1999 (AN) Dakota
1994 – 1999 (BR/BE) Ram Truck
1998 – 1999 (DN) Durango
1994 – 1998 (ZJ) Grand Cherokee
1996 – 1998 (ZG) Grand Cherokee
NOTE: THIS BULLETIN APPLIES TO VEHICLE EQUIPPED WITH A 3.9L, 5.2L. OR
5.9L GASOLINE ENGINE.
An engine intake manifold plenum pan gasket oil leak may occur on some V-6 and V-8
style engines. The oil leak is internal to the engine so no external oil leakage will be
present. Two symptoms of this oil leak condition may be present. The vehicle operator
may experience an engine spark knock during acceleration and/or an increase in the
amount of engine oil consumed by the engine.
Make sure Technical Service Bulletin (TSB) 18-48-98 has been performed.
NOTE: IT IS IMPORTANT THAT THE COIL AND SPARK PLUG WIRES ARE ROUTED
EXACTLY AS SPECIFIED IN TSB 18-48-98 TO ACHIEVE THE MOST
Inspect the Positive Crankcase Ventilation (PCV) valve. Shake the PCV valve to verify
that the pintle inside of the PCV valve is free. Replace the PVC if the pintle is not free.
If the intake manifold plenum pan gasket is leaking, an additional vacuum source will be
created inside of the engine at the location of the pan gasket leakage. Engine combustion
blow-by gases, oil vapor, and air from the crankcase filter/breather may be drawn past the
leaking pan gasket and into the intake manifold. In most cases when this condition occurs,
an engine at idle will create the highest vacuum and lowest amount of engine blow-by.
This bulletin is supplied as technical information only and is not an authorization for repair. No part of this publication may be reproduced, stored in a retrieval system, or
transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without written permission of DaimlerChrysler Corporation.
1. Allow the engine to reach normal operating temperature.
2. Stop the engine.
3. Disconnect the breather hose from the air cleaner.
4. Attach a vacuum / pressure gauge to the end of the breather hose (Figure 1).
1 – VACUUM / PRESSURE GAUGE
2 – BREATHER HOSE
3 – VALVE COVER BREATHER HOSE PORT
5. Disconnect the PCV valve hose from the intake manifold.
6. Seal off the intake manifold PCV valve hose port opening.
7. Seal off the open end of the PCV valve hose (Figure 2).
NOTE: DURING THIS DIAGNOSIS, IT WOULD BE NORMAL FOR THE ENGINE TO
DEVELOP PRESSURE WITHIN THE ENGINE CRANKCASE. THIS IS DUE TO
THE NORMAL PROCESS OF EXHAUST BLOW-BY GASES LEAKING PAST
THE ENGINE PISTON RINGS AND ACCUMULATING IN THE ENGINE
CRANKCASE. DO NOT ALLOW MORE THAN 3 PSI (20.7 kPa) OF
PRESSURE TO BUILD WITHIN THE ENGINE WHEN PERFORMING THE
FOLLOWING DIAGNOSTIC PROCEDURE.
8. Start the warmed engine and observe the vacuum gauge.
9. Allow the engine to idle for approximately 30 seconds. Do not allow more than 3 psi
(20.7 kPa) of pressure to develop in the engine crankcase.
10.If the attached vacuum / pressure gauge does not indicate that a vacuum is present in
the engine crankcase, then the intake manifold plenum pan gasket is good and no
further internal engine vacuum leak diagnosis is required.
11. If an internal vacuum leak is present then perform the Repair Procedure.
I've posted TSB 18-48-98 here http://www.ramforumz.com/showthread.php?t=46269
Be sure you perform this check before tearing into the intake.
|All times are GMT -4. The time now is 09:46 PM.|
Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2015, vBulletin Solutions, Inc.
= Copyright RamForumZ.com a Gigathreads.com Network Site =Ad Management by RedTyger