ZUKIWORLD Online | Suzuki 4x4 Editorial and Forum
ZUKIWORLD Discussion Forum => Suzuki 4x4 Forum => Topic started by: brentd27 on June 10, 2007, 03:38:58 PM
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My dad has a 1995 Suzuki sidekick, stock engine (1.6L 8-Valve), manual transmission. Over the last couple of months it seems like it has lost a majority of it's power taking off from a complete stop. The engine seems to run a little rough at idle. Kinda twitches back and forth while it's idling, and there is a faint gas smell to the exhaust. We changed the plugs, changed the plug wires, checked the plug gaps, distributor, rotor, etc. It seems to be a little better, but still not perfect. We're planning on changing the PCV valve, O2 sensor, and the fuel filter, but was wondering if there is anything else we need to check.
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O2 censor is a good place to start, but I would also check the cat. and adjust the valves!
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Should probably mention that the cat has been cored in an attempt to see if that was the problem. It was definitely clogged.
What is involved in adjusting the valves?
Also, should probably mention that the exhaust header is cracked in two places.
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Do a compession check. Id bet that it has a burned exhaust valve.
Mike
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The haynes manual has good procedures for both adjusting the valves and doing a compresion test it cost ya 20bucks but it's value is priceless for repairs and maintance!
Even if you do a compression test and a cylinder shows up weak you might check the valve adjust ment, sometimes a valve/valve seat will wear faster thant the stem causing a leak like a burnt valve, and an adjustment will get you by for a long time with out having the head re built!
is your Check engine light on? is it working? If the check engine light isn't on but comes on for a few seconds when you start it up, odds are o2 censor is fine!
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Check engine light has been on since they bought the sidekick. I haven't ever had a chance to go through the code reading procedure where you jumper the connector under the hood and watch the blinks.
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Also, should probably mention that the exhaust header is cracked in two places.
The O2 sensor will not work properly if there is any kind of leak around the header. You should replace the header it isn't going to run right until you do.
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Reviving this old thread... We've checked several things, replaced the plugs, wires, O2 sensor, distributor and rotor and it still has some hesitation in the high gears, and will "Cough" and "sputter" every now and then, but the rest of the time it seems to run OK. The high gear thing, to me, sounds like the engine is getting bogged down by a heavy load.
I did a compression test and all 4 cylinders read the same (150 on my gauge. I forget what the units are right now)
Replaced the timing belt this afternoon and the timing looked OK. Don't quite have all the parts back on yet, so we haven't been able to start it up yet to see if it made any difference One question though... When you align the upper and lower timing cogs, which plug wire should the distributor be pointing to? This one points to the plug wire for cylinder 4.
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I think when I did my compression test the minimum compression each cylinder should have was around 175...to me it just sounds like the engine is getting old. A rebuild would put some life back into it. If you don't mind the loss of power just run it as it is....but it will only get worse over time...especially if its burning alot of oil
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If it's a "all of a sudden" problem, maybe you got bad gas or have water in it.Maybe try some dry gas.
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Have you replaced the header yet?
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I had an issue with my air intake plugging up. I cut the intake hose when I did my body lift and had it duct taped together and on a hot day the duct tape released a bit and limited the airflow. It lost power when accelerating.
I had another issue on my van that did the same thing except it turned out to be the MAF (mass air flow) sensor that got dirty when I was using a K & N Filter. The thing sputtered and kicked at high speed. The 1992 1.6l 8v did not have a MAF but I think some models may have because I found a part number for it (http://www.autopart.com/mafs/MAFS1995SUZUKISIDEKICK.htm). I was able to clean the one on the van with some electrical cleaner and a tiny brush.
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After removing the heat shield the header appears to be solid. The cracks I was seeing were only cracks in the surface material
Yes, it was an all of a sudden thing, but it has been through several tanks of gas since then and the problem is still there.
It has never done the missing out or backfiring when I've been riding in it, and the "hesitation" that my dad describes only seems to happen when the car is in fifth gear and going up an incline. It's a standard transmission and due to some problems with my knee joints I can't manage the constant strain of driving a standard, so I haven't been able to test drive it myself and really put it through the paces.
One other thing I should probably mention is that there is a grinding sound shifting into either second or third gear (Can't remember which off the top of my head) and the drain plug on the transmission has had the square 3/8" drive insert stripped out to the point that we haven't been able to remove it for a long time. so there could be some issues there as well.
We put a Spectre cone filter on it first thing after the problems started thinking maybe the air flow was a problem. That was right after coring the cat didn't solve the problem.
The engine doesn't seem to be burning that much oil, and only has some minor seal leaks. It was getting great gas mileage before this happened too, around 29 MPG with the top up, windows down and AC off. Now it's dropped back to about 13-14 MPG.
At this point, I'm suspecting either the MAF or the ECU. Is this a correct line of thinking or could it be purely transmission related?
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The 8 valves don't have an MAF. They started those in 1995 with the 16 valves
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Well, just got back from a test ride and according to my dad it's like driving a whole different car now, so I guess the timing did do some good. Only one minor issue left...
This shows up mostly in low gears, but when you have the throttle at a set position the car will sort of act like it doesn't have any power for a few seconds then it picks up and and you can hear the RPMs increase and there is power to spare. This seems most prominent at low RPMs just after taking off in first or trying to gain speed just shifting in to second.
Does that sound like a TPS sensor?
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Well, the backfiring is back this morning. :( So the timing belt didn't fix the problem.
Where do I go from here?
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Pull the codes from the ECU. Check all round the inlet manifold and throttle body for leaks. Check all the vacuum pipes for perishing, pinholes and blockages.
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ECU is currently not throwing any codes. The light was on but flipping the dummy switch behind the speaker turned it off and it has not come back on.
Checked all the vacuum lines today at lunch and they all seem to be in good shape. Tried disconnecting the electrical connections to the MAP sensor to see what happened and the idle RPMs dropped way down and the engine started smelling very strong like unburned fuel.
The other thing that both of my parents describe just before it backfires is the engine sounding like it is bogging way down almost to the point of dieing, then it will backfire or sputter and regain speed. Seems to happen most frequently right after changing gears, but every now and then will happen as it's just cruising along. Always happens in the lower gears though, never in the higher gears (above third)
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Did an experiment yesterday... Took the MAP sensor off my 1993 tracker that runs like a dream and zip-tied it on to the MAP in my dad's sidekick, swapped the vac line and electrical connection and took it for a test drive... Ran smooth, no stuttering, no backfiring almost no hesitation. Switching back to the original map, the engine has a totally different sound. Sounds deeper, like it's bogged down and gasping for air or something. There's also a definite fuel smell in the engine compartment with the original MAP that goes away when we switch to my MAP. Disconnecting the MAP altogether causes the engine to run real rough, the tone goes even deeper and the fuel smell gets incredibly strong. Am going to check the MAP and the various sensors tomorrow.
I am going to adjust the valves as soon as I get a feeler gauge, and going to tweak the timing as soon as I get a timing light. (Need to make another trip to Harbor Freight. Those guys should really be paying me for advertising.)
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It won't run too well without the MAP sensor, the ECU relies on that to calculate fuelling. There should be a small filter in the vacuum line to the MAP sensor, that could be plugged or damaged. If the filter is missing/damaged then the sensor will get contaminated from being exposed to fumes. I believe that the filter also provides some damping of the vacuum pulses.
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I looked at that filter thinking it was a check valve, but it doesn't seem to be too restricted. When I did the MAP swap from y tracker to his Suzuki, I did not swap filters.
If you buy a new MAP do those filters come with it or is there a separate part number?