- This topic has 10 replies, 3 voices, and was last updated 11 years, 5 months ago by
.
-
Topic
-
A issue with one of my cars has gotten to the point where it can not be ignored any longer(used to be intermittent but now is all the time).
Issue: Has low idle in drive and lacks power at low RPM’s(under load), but is fine when sitting at idle(in park) or at high RPM’s(under load).
Car:1996 Suzuki Esteem GL 4 door sedan 1.6L Automatic Trans 140K miles
Codes:No codes present
Items checked:Air filter- Fuel filter, pressure(no meter to measure flow but bypass on pressure gauge seams to flow well), and pump- Ign, Spark plugs, cap, rotor, wires.
Items tested:Compression All 4 between 100-105PSI-Vacumme(at idle)10-12Hg(3500ft elev)Throttle snap it goes from 10 to 0 then to 20 then back to 10
exhaust doesn’t seam restricted(like from a cat if it was plugged)Well that’s all I can think of to tell you at moment, but if you need more info just ask. The wife drives this car mostly(it her grocery getter), so reliability is very important in this car. Please any ideas of where to go next without throwing a grip of parts at it would be great.
THANKS
-
Replies
-
Try cleaning the throttle body. The idle air valve may
not be working or is dirty. If the vehicle has a working
ac.Turn it on see if the idle picks up. if not Iac needs
cleaning or replacement.I would also like to add that the
egr could be leaking by and or the passages full of carbon.+1 on all that, and perhaps check the throttle position sensor or the camshaft position sensor. I had similar problems on a Nissan truck a few months ago. Turned out the camshaft position sensor was dead and knocked off idle timing quite a bit.
KK throttle body butterfly opened it and cleaned it out with shop rag and map sensor cleaner at same time sprayed off Air temp sensor(just for the heck of it). Haven’t removed the EGR yet but at idle if apply vacuum, it does nearly stall the engine(so assume it isn’t stuck open)and held vacuum so diaphragm not leaking. One thing I forgot to mention is that being that it seams to be more apparent when manifold is in a vacuum state(low RPMs and/or under load) I searched high and low for a vacuum leak and found none. When I depress the accelerator pedal there does seam to be like a dead spot but it is hard to tell if it is from worn TPS or just from the hesitation that is there at low RPM’s(really hope it not a TPS local parts store wants nearly $200 for it and it special order only).Pulled the CKS out today(easy on bottom of oil pan 10mm bolt) it had a little oil residue build up on it, but nothing that seamed that severe. 6 months ago replaced timing belt and water pump but thought that could not be the issue because at first it was intermittent(and jumped timing wouldn’t be). Now it not intermittent but still don’t think it has jumped timing. Until yesterday when I had it on the scanner(I might have miss read it) thought it was reading at 5 ATDC not 10 BTDC, but got pulled away and haven’t had a chance to double check that reading yet. But like I said jumped timing wouldn’t be intermittent I believe. Was wondering if the Knock sensor would advance the timing cause it does kind of knock when it is doing this? As far as test procedures for the Knock and TPS, kind of hard to find lately with Suzuki pulling out of the US marketplace. So if anyone has access to correct readings and procedures and would like to share them with me, I would be very thankful(otherwise I just have to assume how to and what they should be). Was also wondering could a faulty/lazy upstream O2 sensor cause it to act this way(again got pulled away but thought it was staying around -6% on the STFT when had it on the scanner for those few minutes)? Hope tomorrow to get the time to re-scan it and confirm some of these readings.
Your fuel trim is subtracting fuel. Your vacuum level
at idle is low. hook up the vacuum gauge and remove
the front o2 sensor and run the vehicle see if vacuum
comes up.Here are a few screenshots of my scanner readings.
COLDWARM
WARM IN PARK RAISED RPM’S
IDLE/WARM IN DRIVE
Your fuel trim is suggesting the system finds too much gasoline in relation to the amount of air taken in. Your MAP sensor shows up as working at least, so perhaps it’s a exhaust leak before the Oxygen sensor?
The typical goto list would be something like
– defective MAF
– defective O2 sensor
– Too high fuel pressure / defective fuel pressure regulator
– Defective (leaking) injectors
– Timing is offYour engine coolant seems to show up as normal. Your timing seems to be 13° when warm, which I believe is normal for your car. rpm in idle are around the normal 700 to 800 range too.
What I find a bit odd is that your cold reading is closed loop, which would suggest something fishy about the o2 sensor readings, as it should be in an open loop until the sensor reaches a higher temperature.
I know I said cold in the description, but it was at least 97 degrees outside when I first started the car that day.
No signs of leakage at exhaust manifold gasket or cracks in manifold(upstream O2 in the exhaust manifold).
The readings on the O2 seam to be slow or not a responsive as I would expect(usually they flip-flop +-+-+-quickly, mine just kind of hangs more – then will for a second go + then back – for a few)so maybe it starting to go out getting lazy readings not exactly sure what the response times should be for a single wire O2.Going to try like said removing O2 and checking vacuum in morning although it will give me the same results as when I disconnected the exhaust at the 2 pipesshown.
As far as checking actual fuel pressure with car running, I am waiting for a adapter I had to order, because Suzuki was not kind enough to place a Schrader valve in the line any where. And also which is really strange the manual says it uses manifold vacuum to regulate it but the regulator has no where to attach a vacuum line to it, so not sure if it uses some type of spring or sealed chamber to regulate it with(my car is June 95 and manual is for a 96, but hell should still be same).Every thing looks same except there is no #8 as shown in the image.
Personally I am kind of leaning towards O2 or TPS(SSOOOO hope not this so expensive), have replaced O2(50K and at 90K) twice in life of the car but they do go defective. Scares me that the TPS just doesn’t seam as smooth in its ranging as you think it would be. Also going to check in morning the IAC system, because don’t think it is cause of my issue but still AC on/off not only didn’t bump up the idle but at same time didn’t seam to cause any more of a load on the engine even though compressor was cycled on.
If you wonder why am so worried about it being the TPS read here because it is almost the same issue:
https://www.ericthecarguy.com/kunena/8-Service-and-Repair-Questions-Answered-Here/46011-maf-sensor-cost-huge-differences-whyJust wondering if a slightly wobbling harmonic balancer could cause the issue’s I am having????
AH, let me see if I can still work my camera and I’ll post a video of it.Here is a short video showing the issue. Sorry for bad sound, I know it is no where near E’s quality.
http://www.youtube.com/watch?v=wcR_groyF7I&feature=youtu.be
OK I don’t know why I can’t get the link to post?
- You must be logged in to reply to this topic.