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Discussion Starter · #1 ·
Hello,

Over a year ago the idler pulley seized on my 98 Rodeo 2.2 sending the cam belt out through the timing cover and crashing the valves.

I've swapped in a recon head and got the engine more or less running, but have failed a few times to get it through the smog test. It ran quite well for the first 25 miles (when I was readying the ODBII for the smog test) but then CEL came on as I arrived at the test station (cylinder 3 misfire). I changed plugs and wires and tried again, but the next time engine had a very slight misfire on way to test station and then would not idle smoothly to hold the 15mph test. The test was abandoned.

Since then I've only done a few laps of the block and misfire has got worse. The car idles pretty nicely at 800rpm on the driveway, but then bucks like crazy as I accelerate up into 2nd gear. You can almost drive through it by putting foot to floor.

The CEL light stays off (apart from when I disconnect sensors - so I also suppose the PCM is OK)

I've also checked following:

I get about 21 inches of vacuum at idle

I've not found any vacuum leaks using a hose, spraying soapy water etc

I can hear all the injectors ticking away.

Compression is 145-155 across the 4 cylinders

MAP, IAT, O2, TP, VSS, ECT sensors seems to work OK (I have a USB scan tool that charts the data - great value for about $40 & I've also followed Haynes checks)

Timing marks seem to line up OK (as close as I can get anyway, without going a whole extra tooth out)

Also I have changed the plugs, wires, air and fuel filters.

Then I have following deviations / queries from the Haynes manual.

1: : Idle speed stays constant when I disconnect the IAC valve (though both IAC coils seem intact and pintle definitely moves under PCM control)

2: The coil pack connection order seems to be 1432 (not 1342 as shown in the Haynes Manual)

3: I can't find anywhere what the connection is at the back of engine, right next to the coil pack (like a copper nail head, with a female spade connector that slips over it). It was disconnected for a while. Now reconnected

4: I think I have a linear EGR, so can't check this.

5: I don't have PCV, Thermac or AIR system?

Also have noticed the following:

6: manifold vacuum erratically drops to almost atmospheric when engine is bucking (both on MAP chart from scan tool and also a vacuum gage that I set up in the cab)

https://lh5.googleusercontent.com/-B1y_ ... 2520PM.jpg

(Left side of chart is idle, then a short test drive, right side is engine stopped)

7: my inductive timing light reads 2X the revs when hooked to wire 1. Also the flash is a little erratic.

I've been chasing the Smog test problem around and around since the beginning of the year (I only get to 'touch' the car every few weeks, or so)

It would be great if anyone can confirm 1-5..

On 6 & 7 I'm curious if a fuel issue (say fuel blockage at the injectors) could cause ignition to be erratic. Or is the irregular timing light flash a sure sign something is wrong with the coil etc?

I've not been able to figure out how I can even test the injectors?

Or anything else (even if it's advice to give up and scrap the car)

Many thanks in advance, if anyone can help.

Pete
 

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Not much help since I've never worked on a 2.2. I will say that on my Mitsubishi Might Max I killed the MAF sensor. Every thing seemed fine at idle and at low humidity. But if I was driving and humidity was above 30% it would buck like crazy. Even took it to a dealer and all they could find wrong was a loose intake tube clamp. I eventually replaced the MAF with one from a salvage yard and everything was fine after that. Might give you somewhere to look at least.
 

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Discussion Starter · #3 ·
Thanks for the advice!

I forgot to say in my earlier post that I don't think I've got a MAF. I have looked, and would be glad to change it /check it if I do have one.
 

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I had a 99 amigo with the 2.2l I had a bad missfire, turned out I was getting oil down in the spark plug wells and grounded out 1 of the plugs. There are O rings that go on the bottom side of the valve cover where the valve cover bolts go through. If one of those O rings cracks, oil will leak into a spark plug well and give you a miss fire. Pull your plug wires and check them for oil.

Scott
 

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Discussion Starter · #5 ·
Thanks. That makes sense too, as I did notice the new plugs were very wet with oil when I took them out to do the compression test today. I'll replace the O rings, clean everything up and report back when I can.
 

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Discussion Starter · #6 ·
Hi, grateful if anyone with a 2.2XE can confirm if their coil pack connection is also 1432 (not 1342, as shown in Haynes manual). I'm still chasing that misfire around and around, and it would be lovely to rule this out. Thanks.
 

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Discussion Starter · #7 ·
scott said:
I had a 99 amigo with the 2.2l I had a bad missfire, turned out I was getting oil down in the spark plug wells and grounded out 1 of the plugs. There are O rings that go on the bottom side of the valve cover where the valve cover bolts go through. If one of those O rings cracks, oil will leak into a spark plug well and give you a miss fire. Pull your plug wires and check them for oil.

Scott
I did check, and found actually that that central 'well' was entirely clean and dry.

(The oil I'd seen on the plugs was actually from a dirty socket that I had used to remove them, since the rocker cover was leaking badly before the cam belt broke and the old plugs were soaked in oil. I had already replaced the rocker cover gasket when I changed the head.)

Incidently I checked the cam cap bolts whilst cover was off, and found several were only just 'snug'. Almost loose.

I'd tried to use a foot lb torque wrench to set the 71 inch lbs (set to about 6 ft lbs) ...so I've learnt that that is not a good plan since it was not evidently accurate enough. I need to get a inch lb torque wrench...one more thing to eliminate.

Thanks for the suggestion!
 

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Discussion Starter · #8 ·
Still working on this...

To start with, I'm still convinced my coil pack connection order is 1432 on this '98 2.2 Rodeo. I'd be grateful if anyone can confirm this on their 2.2, just to eliminate one more thing.

Meanwhile, I found a new puzzle today when I hooked up my inductive timing light today.

The car idles reasonably well at 800 RPM, but bucks like crazy if I try to drive it.

With the timing light:

Leads 1 & 3 show 1590 - 1610 RPM and flash is regular.

Lead #2 shows about 800 rpm and flash is intermittent

Lead 4 shows rapm ranging from about 800 to 1600 and flash is also intermittent

The rev counter and ODBII scanner show a fairly steady 800 rpm.

I suppose the coil pack needs replacement (leads and spark plugs are already new) but I'm surprised I don't have any engine misfire codes showing on the OBDII.

Whilst I'm asking for help, the engine revs don't change either when I disconnect the IAC connector (as described in the Haynes manual, for the diagnostic check)

Any advice would be gratefully received before I spend even more $dollars replacing any more expensive parts, which subsequently turn out not to have solved the issue.

Thanks everyone... P
 

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I have never worked on a 2.2L, but from info posted in the forum the correct firing order for the 2.2 L is 1432 and the cylinders are numbered 1234 front to back. Typically 2 spark plugs share a single coil. One plug is connected to one end of the coil secondary winding and the other plug to the opposite end of the secondary winding. When one cylinder is at TDC on the firing stroke the other is at TDC on the exhaust stroke and both plugs fire at the same time. This is known as "Wasted Spark" ignition. Your test indicates there is a problem with the 2 & 4 coil.
 

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Discussion Starter · #10 ·
Hi, thanks for the reply.

I'm still a little perplexed by my test, since I assumed that plugs 1 and 4 were connected to one coil and 2 & 3 would be connected to the second coil.

That conflicts with my test that is showing 2 & 4 are misbehaving. Perhaps both coils are bad, but I'm still suspicious something else is wrong.

Still, I've found I can get coil packs from ebay for about $40, which is less painful to swallow than the $280 I saw from the regular car spares places.

I'll replace the coil pack anyway and see if that helps.

BR P
 

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Discussion Starter · #11 ·
Here is a photo of the coil pack



I would have guessed that this unit was split into 2 coils.

Coil 1 as the bottom half of this photo and coil 2 as the upper half.

Then I would have guessed the coil firing order alternated between upper and lower coils like this:

Coil 1 - Cyl 1
Coil 2 - Cyl 4
Coil 1 - Cyl 3
Coil 2 - Cyl 2

Except that does now not make sense either, since I have the wires hooked up in this order (from bottom to top in the photo - 1432)

Which means that the sequence would be like this, with each coil firing twice in a row?

Coil 1 - Cyl 1
Coil 1 - Cyl 4
Coil 2 - Cyl 3
Coil 2 - Cyl 2

My guess is firing order is actually 1342 (correct in Haynes) with coil pack connection as 1432 (incorrect in Haynes)

giving this sequence

Coil 1 - Cyl 1
Coil 2 - Cyl 3
Coil 1 - Cyl 4
Coil 2 - Cyl 2

Which still doesn't really explain why I have a good spark on 1&3 and a poor spark on 4 & 2.

Any thoughts anyone?

BR P
 

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In order to sort this out you need to determine which cylinder is at TDC exhaust when #1 is at TDC on compression.
If it is #4 the coil hookup is 1&4, 3&2
If it is #3 the coil hookup is 1&3, 4&2

I think the correct coil hookup is 1432 and the firing order is 1342 which accounts for the confusion.
 

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Discussion Starter · #13 ·
I've replaced the coil pack, but it did not fix the issue.

I can at least confirm the coil pack hook up is 14 23, which makes sense.

The hook up order was molded into both the old and new coil packs, which I could not see when coil pack is bolted to back of engine.

The car still idles nicely on the drive out of gear, will even run down the road in first gear with almost no throttle. Then bucks like crazy if i gently press the throttle in first gear, though I can put my foot down hard and it does not buck, but does not pull hard either.

I've tried propane to look for vacuum leaks with no effect. I can hear a slight hiss around the EGR (?) mounted on the left rear (drivers side) corner of the engine, when I listen with a piece of plastic tube, but don't see any vacuum lines thereabouts (?).

The timing light is still flashing erratically.

I'm running out of things to check / replace now. One person mentioned the IAC (which also tie in with Haynes manual, since the revs don't change when I disconnect the connector), but that erratic flash bothers me, as I can't really see that that would be related to the IAC. Also I've checked the IAC coils which are OK and it seems to move freely. I guess I'l have to go for it, but it's over $200 and I suspect it's fine.

As usual, any thoughts would be welcome. BR, Pete
 

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hi, I am not familiar with your engine. The IAC would only turn-on when engine rpm drops > like air conditioning turned-on or something similar.
Leave it disconnected, i bet it still bucks !!! Look elsewhere. my 2 cents.
 

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Discussion Starter · #15 ·
That's a great idea Dave. I'll try that.

I'm also going to find a way to take a look at the injectors, as I've read that the wasted spark system relies on the mixture in the two cylinders to give a stronger spark in the firing cylinder, compared to the exhaust cylinder. Plus check again for vacuum leaks.

I can imagine that an erratic mixture then manifests itself as an erratic spark.

Long shot, I know.
 

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Discussion Starter · #16 ·
Hmmmn. I disconnected the IAC, started the car and set off down the street without letting it warm up. I made it about 50 yds (still bucking) but barely made it back. I had to ride the clutch in 1st gear to crawl back at less than walking pace, with almost no power at all.

I can't tell if that was really the effect of the IAC, or the underlying condition is deteriorating.

I had another listen to that hiss around the EGR and I suspect it's positive pressure, not a vacuum leak (I put some bubbles down my listening tube, and they tended to move up when I got close to leak, no sucked down - not definitive, though). It's awkward to get to at the back of the engine and I can't really see much at all down there. I squirted more propane around the area and see no change in the revs, as far as I can tell.

To be continued...
 

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Have you checked your engine ground wires, one on each side of the engine. I have had problems with my 2.2l, hanging RPMs. cleaned ground contacts and the problem cleared up.
 

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Have you found your problem with the misfire? mine started misfiring got a flashing engine light and a bad misfire now?? took it to friends shop and had a 1404 code and the scanner said random misfire.. :bom:
 

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Discussion Starter · #19 ·
Sadly no... I still have no engine codes, car idles well but has no power at all. ]

(My only clue is I hear what I suspect is a vacuum leak right around the back of the engine, closest to the firewall, around the EGR. I've tightened every thing I can find, but I still hear the hiss and still have the problem.)

Good luck with your problem... BR P
 

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paj99 said:
Sadly no... I still have no engine codes, car idles well but has no power at all. ]

(My only clue is I hear what I suspect is a vacuum leak right around the back of the engine, closest to the firewall, around the EGR. I've tightened every thing I can find, but I still hear the hiss and still have the problem.)

Good luck with your problem... BR P
Have you checked your cat to see if its plugged that would make it buck and not let you give it any gas as it cant exit the exhaust..

I'm going to replace the camshaft position sensor and the crank sensor i have a new coil pack,plugs,wires,mine started this after i got my exhaust fixed ?? i have no cat and it has a flow master 40 series muffler ..lol sounds ok i guess..But that would not make it misfire! ill update you if i find the problem! also i was told that the plugs need to be platinum plated and gaped to spec on the 2.2 DOHC...
 
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