Avensis 1.8 Vvti Coil Pack

[henni]

Hi

First post! Registerred previously as meant to ask about dog crates/guards but had not got to do it!

Just on an off chance had to call RAC late yesterday when misfire started followed immediately by engine management warning light. Got car home and they kindly diagnosied and proved no3 cylinder coil pack needs replacing.

All set up to fit -they have reset warning light, but I can't find one to get today, was going to Norwich, as was hoping to fit and use car tomorrow. Appreciate any suggestions. Also Europarts/mpd quoting £64 aftermarket .

Thanks very much

Chris

[fastbob72]

Sorry don't quite follow what you're asking but and let me know if I've picked you up wrong.

You need a new coil on plug for no. 3 but you can't get one right now so are you asking whether it's ok to drive till you get one tomorrow??

If that's what you mean the answer is it's your call i wouldn't advise you to do something that could damage your car.It's basically like driving any car with a faulty lead or plug, it ain't good for it at all but it probably won't do catastrophic damage driving a couple of miles but it's not for me to say it is your choice.

Is it misfiring regularly like it's on 3 cylinders or barely noticeable but tripping the management light and going into limp home mode.

Again I'm extremely loathe to say anything that may convince you it's ok and you make the car worse, if it was me I'd probably drive her easy the 10 miles from mine to pick. up a new coil pack but only if i absolutely couldn't get a lift or it picked up.

[henni]

Thanks Fastbob for taking the time to reply. I was just seeing if anybody new of a part I could pick up today, but appreciate your comment about driving with 1 cylinder out. I limped it home a couple of miles yesterday, but will leave it until I can hopefully pick up the part and fix it tomorrow night.

[Konrad C]

Also it takes only a few minutes to change. Keep that receipt just in case.

Good advice from FastBob.

[avensisd4d786]

The VVTI has pencil coils so I would replace the faulty one, I would normally get part number of top of coil and put it on eBay and buy a used genuine one. should be able to get under £20.

I do not like going aftermarket with something like that.

I recently worked on a 1.4 VVTI with a misfire on cylinder 3.

I wasn't sure when the plugs were changed so we decided to change them before changing the coil after changing to NGK plugs we got the car running on 4 cylinders.

if you are unsure when the plugs were changed or if its been a while, wont harm in changing them they cost me around £2 each.

this video may help too.

[henni]

Thanks for the comments and replies, very helpful. I shall have to get a coil pack tomorrow, but will also look to get a least one more used genuine off eBay, as I have been warned that once one goes the others may well follow. I have only had the car - 2002 reg 4 months -had a saloon 1.8 Avensis 1999 prior to that for 3 years and had never had any issues before, hence seeking another albeit an estate this time.

Again appreciate the comments.

[fastbob72]

The VVTI has pencil coils so I would replace the faulty one, I would normally get part number of top of coil and put it on ebay and buy a used genuine one. should be able to get under £20.

I do not like going aftermarket with something like that.

I recently worked on a 1.4 VVTI with a misfire on cylinder 3.

I wasn't sure when the plugs were changed so we decided to change them before changing the coil after changing to NGK plugs we got the car running on 4 cylinders.

if you are unsure when the plugs were changed or if its been a while, wont harm in changing them they cost me around £2 each.

this video may help too.

Ah right after reading your answer i understand the OPs query and appologise to him for being slow lol

I've had a Ford Escort RS1600i with the twin coils (and can I say for the 100,000th time online but it's still worth stating the only really good CVH engine Ford made. The RS Turbo ok to good, RS1600i very, very good. All other CVHs only fit to be boat anchors..... that Escort was one of the best hot hatches and most underrated of the 80s and 90s sorry for that lol)..... I had a Nissan 200SX with coil packs and my vvti i have now. I've never replaced one or had any problems so I can't say with any certainty that there is an issue or there isn't with mixing OE and aftermarket coil packs.

I can see the cause for concern in doing so along with the desire to replace them as a set but if you think objectively about your engine for a moment. There are quite a lot of factory variables in a road car engine. Have built a number several fast road/semi race engines for my cars over the years and it's surprising the degree of variance between the cylinders. Anyone who's done a compression test will have seen there may be several psi between them, the tolerance usually being under 10 psi between best and worst is acceptable. Again if you've ever CC'd your combustion chambers you'll kniw there's a wide scope for variance. It's why a blueprinted engine is still something of worth.

The point is that to think the quality of combustion between cylinders isn't as exact as you would imagine. The number of factors involved are many and few of them are identical across the cylinders so to imagine there is a real world effect from running 3 OE packs and one AM that would in anyway reduce the engines output in real time or over time is probably being too critical for a road car engine unless it was modified for power and spent a lot of time near the redline.

I suppose you could measure the resistance of the 3. OE coils and th e AM one with a multimeter and disconnected completely.

With normal coils and HT leads you'll find there's a resistance range for prmary n secondary resistance cold and hot. It's often something like 10 to 16K ohms for example. Have just skimmed thru my haynes for the Avensis which covers my 52 1.8vvti and it doesn't have any measurements but if you had a multimeter you could test the 3 noting their similarity or difference then test the AM anf if it's similar to the first three especially if near the average of the 3 OE packs then It's safe to assume the performance will be likewise and certainly well within the requirements of a road car engine. You could then measure the faulty coil and note the difference out of interest of nothing else.

It's like fitting spark plugs you'd balk at the idea of fitting 3 Bosch and an NGK, I would myself yet if you were to measure each cylinder individually if possible for combustion pressures,for what levels of HC, Nox and CO2 were produced and a range of other tests I suspect the differences would be negligible to say the least.

So unless it states anywhere invthe Toyota handbook that fitting different coil packs is inadvisable and can cause problems or even engine damage then I think there is little to worry about. Coil packs aren't digital in that they deteriorate, their performance will fade over time and use. So the quality between 3 OE coils eould probably be wider between worst and best than between anh of the 3 and the AM one.

Again this is my opinion having not gone right into the performance and quality of OE vs AM coils or reading manufacturers advice so it's my opinion only.

The thing to remember is though any coil pack. in each cylinder of any engine has one main task which is to deliver a good,quality spark at exactly at the right amount of crankshaft rotation so it travels to the spark plug at a know speed to effectively time a spark to jump the plug gap when the piston reaches the optimal position a specificnumber of degrees BTDC so the expanding gases propel the piston back down with the most ideal level of pressure and momentum.

The AM coil pack has to reach the same precise performance level as OE coils so I see no issues beyond it just doesn't sit right not having a full set of the same make and age.

Like I say three Champions and a Halfords plug just feels wrong but all parameters they will meet are the same for each application so they have to attain the same standard...... feels wrong, sits wrong yet I bet completely harmless :)

[fastbob72]

The VVTI has pencil coils so I would replace the faulty one, I would normally get part number of top of coil and put it on ebay and buy a used genuine one. should be able to get under £20.

I do not like going aftermarket with something like that.

I recently worked on a 1.4 VVTI with a misfire on cylinder 3.

I wasn't sure when the plugs were changed so we decided to change them before changing the coil after changing to NGK plugs we got the car running on 4 cylinders.

if you are unsure when the plugs were changed or if its been a while, wont harm in changing them they cost me around £2 each.

this video may help too.

Ah right after reading your answer i understand the OPs query and appologise to him for being slow lol

I've had a Ford Escort RS1600i with the twin coils (and can I say for the 100,000th time online but it's still worth stating the only really good CVH engine Ford made. The RS Turbo ok to good, RS1600i very, very good. All other CVHs only fit to be boat anchors..... that Escort was one of the best hot hatches and most underrated of the 80s and 90s sorry for that lol)..... I had a Nissan 200SX with coil packs and my vvti i have now. I've never replaced one or had any problems so I can't say with any certainty that there is an issue or there isn't with mixing OE and aftermarket coil packs.

I can see the cause for concern in doing so along with the desire to replace them as a set but if you think objectively about your engine for a moment. There are quite a lot of factory variables in a road car engine. Have built a number several fast road/semi race engines for my cars over the years and it's surprising the degree of variance between the cylinders. Anyone who's done a compression test will have seen there may be several psi between them, the tolerance usually being under 10 psi between best and worst is acceptable. Again if you've ever CC'd your combustion chambers you'll kniw there's a wide scope for variance. It's why a blueprinted engine is still something of worth.

The point is that to think the quality of combustion between cylinders isn't as exact as you would imagine. The number of factors involved are many and few of them are identical across the cylinders so to imagine there is a real world effect from running 3 OE packs and one AM that would in anyway reduce the engines output in real time or over time is probably being too critical for a road car engine unless it was modified for power and spent a lot of time near the redline.

I suppose you could measure the resistance of the 3. OE coils and th e AM one with a multimeter and disconnected completely.

With normal coils and HT leads you'll find there's a resistance range for prmary n secondary resistance cold and hot. It's often something like 10 to 16K ohms for example. Have just skimmed thru my haynes for the Avensis which covers my 52 1.8vvti and it doesn't have any measurements but if you had a multimeter you could test the 3 noting their similarity or difference then test the AM anf if it's similar to the first three especially if near the average of the 3 OE packs then It's safe to assume the performance will be likewise and certainly well within the requirements of a road car engine. You could then measure the faulty coil and note the difference out of interest of nothing else.

It's like fitting spark plugs you'd balk at the idea of fitting 3 Bosch and an NGK, I would myself yet if you were to measure each cylinder individually if possible for combustion pressures,for what levels of HC, Nox and CO2 were produced and a range of other tests I suspect the differences would be negligible to say the least.

So unless it states anywhere invthe Toyota handbook that fitting different coil packs is inadvisable and can cause problems or even engine damage then I think there is little to worry about. Coil packs aren't digital in that they deteriorate, their performance will fade over time and use. So the quality between 3 OE coils eould probably be wider between worst and best than between anh of the 3 and the AM one.

Again this is my opinion having not gone right into the performance and quality of OE vs AM coils or reading manufacturers advice so it's my opinion only.

The thing to remember is though any coil pack. in each cylinder of any engine has one main task which is to deliver a good,quality spark at exactly at the right amount of crankshaft rotation so it travels to the spark plug at a know speed to effectively time a spark to jump the plug gap when the piston reaches the optimal position a specificnumber of degrees BTDC so the expanding gases propel the piston back down with the most ideal level of pressure and momentum.

The AM coil pack has to reach the same precise performance level as OE coils so I see no issues beyond it just doesn't sit right not having a full set of the same make and age.

Like I say three Champions and a Halfords plug just feels wrong but all parameters they will meet are the same for each application so they have to attain the same standard...... feels wrong, sits wrong yet I bet completely harmless :)

[captain avensis]

Hi

Just had the same problem and replaced number 3 coil pack with AM one. car runs fine but engine management light comes on after 15 minutes. disconnect Battery /reconnect and the same thing happens. Initially ran the car on 3 for a few miles to get home...have I messed up the catalytic converter in the process? please can someone advise me on this, as I am tearing my hair out! I hate warning lights being on!

cheers

[Konrad C]

You need to buy an ODBII (OBD2) code reader to obtain the codes. They don't cost much if you try eBay. Cheaper than taking it to the garage.

When you get the code reader just plug it into the OBD socket located behind the storage box, by your right knee. This is where the internal fuses are.

You will get the codes for the misfire and anything else that may be stored.

May be one of the members can recommend a good brand.

Regarding the after market coil pack, if the scanner still reports the same cylinder, especially after you have cleared the codes, then it is faulty or not compatible.

The other issue could be Cat or O2 sensor damage.

Wait until you get the diagnostics check before doing anything.

[captain avensis]

thanks for the quick reply!

I will get the code reader .

many thanks

Captain Avensis

[henni]

Hi

Sorry did not get back yesterday, but read the reply you received. I would say the same. I had called the RAC initially as I did not know what was wrong. Their diagnosis was spot on but before he left he reset the code so that the warning light went off and I did not run the car until I was able to fit the new coil pack the next day. I looked to but a diagnosis/reset tool from Amazon for about £50 but have not done so yet!

The only twist to my tale was that the aftermarket coil I bought had a slight misfire under load, so by the end of the week I took it back and was refunded. In the meantime I had bought a genuine but used 1 off eBay for £10 and this has worked perfectly (i then bought another as a spare!)

Suprised by your picture as my Avensis estate is identical, colour trims etc just 2002! Tried to source a genuine dog guard for it but haven't found one yet.

Hope you got sorted

Regards Chris

[fastbob72]

I would also add that on a few occasions when I've either changed my plugs or disconnected the coil packs for some reason I've found it registering a fault code, usually a cylinder misfire or a coil pack fault that persists but after clearing the fault code it didn't return.

It seems that simply disconnecting parts of the ignition system throws up a code.

The last few days I've unplugged the multiplug to the Oil Control Valve, firstly to test the signal to the OCV and check the the resistance too. Every time it's disconnected then plugged back in it registers a fault code which I clear, job done.

I've noticed it happen with the coil packs too but not necessarily every time unlike the OCV

[fastbob72]

I had a stroke of real luck recently finding 2 T22 1.8 vvtis i the scrappies..... one had an immaculate engine with all 4 coil packs looking like they had been recently replaced before the car was scrapped so I bought all 4 plus the door loom to electric window motor in my drivers door that badly needed replaced for the princely sum of 5 quid........ bargain of the century lol.

I've kept my cars on the road and had some amazing finds from the same place for the last 25 years...... the same 5 pounds got me a pair of twin 40 DCNFs plus manifold and linkages that I adapted to fit my XR2 at the time,they came from an early MG Meastro...... remember them lol

[captain avensis]

bought the code reader for £11

came up with code for oxygen sensor on exhaust manifold.

bought replacement for £20 and fitted.

No more codes no more engine light. no problem.

This forum is excellent. Thanks to good advice !

I love Toyoya people !!